CSPIQ · AP Computer Science Principles

CSPIQ Mock Exam 2 — AP Computer Science Principles

Full Section I Simulation (Final Form)

Time: 120 minutes · 70 questions · No calculator (none needed) Format: Q1–57 single-select · Q58–62 reading passage + 5 single-select · Q63–70 multiple-select ("Select two answers")

Instructions: Take this exam in one timed sitting after reviewing your Mock 1 misses. The code-analysis items here run slightly harder than Mock 1 — multi-procedure traces, loops inside loops, robot journeys with iteration — matching the tougher end of real exam forms. Answer everything; unanswered = 0%, guessed = at least 25%.

Questions 1–57: Single-Select

Question 1

What is displayed?

count ← 10
count ← count MOD 4
count ← count * count
DISPLAY (count)

(A) 100
(B) 16
(C) 2
(D) 4

Question 2

A program's requirements state: "Users must be able to undo their last entry." This statement describes:

(A) The program's syntax
(B) An overflow condition
(C) An intended behavior the finished program should exhibit
(D) A run-time error

Question 3

The largest whole number that can be represented with 7 unsigned bits is:

(A) 127
(B) 128
(C) 7
(D) 64

Question 4

What does h(6) return?

PROCEDURE h(n)
{
    total ← 0
    REPEAT UNTIL (n ≤ 0)
    {
        total ← total + n
        n ← n − 2
    }
    RETURN (total)
}

(A) 6
(B) 12
(C) 8
(D) 10

Question 5

A librarian scans a returned book; the system plays a chime and updates the availability database. The scan event, chime, and database entry are, respectively:

(A) Output, input, metadata
(B) Metadata, output, input
(C) Purpose, function, purpose
(D) Input, output, output

Question 6

Two datasets can be meaningfully combined when:

(A) They share a common field linking their records
(B) They are the same size
(C) Both are compressed
(D) Both are sorted alphabetically

Question 7

What is the list after this code runs?

L ← [7, 2, 9, 4]
REMOVE(L, 3)
INSERT(L, 3, 5)
APPEND(L, 2)

(A) [7, 2, 9, 5, 2]
(B) [7, 5, 2, 4, 2]
(C) [7, 2, 5, 4, 2]
(D) [5, 7, 2, 4, 2]

Question 8

A weather simulation assumes rainfall is identical across an entire county. Its flood predictions for specific neighborhoods will be:

(A) Exact, because simulations compute precisely
(B) Improved by the assumption
(C) Unaffected by the assumption
(D) Unreliable where real rainfall varies locally — the simplification erased the variation that flooding depends on

Question 9

Which expression is true exactly when x is between 20 and 40, EXCLUSIVE of both endpoints?

(A) x ≥ 20 AND x ≤ 40
(B) x > 20 AND x < 40
(C) x > 20 OR x < 40
(D) NOT (x < 20 AND x > 40)

Question 10

A analytics program reads a 4-million-row table and must report the number of rows where status = "active". The appropriate operations are:

(A) Filter by the condition, then count the surviving rows
(B) Sort by status, then count all rows
(C) Count all rows, then filter
(D) Combine the table with itself

Question 11

What is displayed?

s ← ""
FOR EACH c IN ["x", "y", "z"]
{
    s ← c + s
}
DISPLAY (s)

(A) xyz
(B) xxyyzz
(C) zyx
(D) xyzxyz

Question 12

After this code, what is b?

a ← 3
b ← 7
IF (a > b)
{
    b ← a
}
IF (a < b)
{
    b ← b − a
}

(A) 7
(B) 3
(C) 10
(D) 4

Question 13

A student claims her sorting algorithm runs in unreasonable time. To be correct, the algorithm's step count must grow:

(A) Linearly with the list's length
(B) Exponentially (or worse) with the input size
(C) By a constant amount per element
(D) As the square of the input size

Question 14

RANDOM(3, 7) + RANDOM(3, 7) can produce how many DIFFERENT values?

(A) 9
(B) 25
(C) 10
(D) 5

Question 15

A robot on an open 4×4 grid starts in the bottom-left square facing north and runs:

REPEAT 2 TIMES
{
    MOVE_FORWARD()
    MOVE_FORWARD()
    MOVE_FORWARD()
    ROTATE_RIGHT()
}

Where does it end?

(A) Bottom-right square, facing south
(B) Top-left square, facing east
(C) Top-right square, facing south
(D) Center of the grid, facing west

Question 16

Which best describes why a program that works correctly can still produce biased outcomes?

(A) The outcomes reflect the data and assumptions built into the system, which can carry bias without any code error
(B) Correct programs cannot produce biased outcomes
(C) Bias is a type of syntax error
(D) Computers introduce randomness into all results

Question 17

What is displayed?

nums ← [2, 4, 6]
i ← 1
total ← 0
REPEAT 3 TIMES
{
    total ← total + nums[i]
    i ← i + 1
}
DISPLAY (total + i)

(A) 12
(B) 15
(C) 13
(D) 16

Question 18

Which scenario describes a rogue access point?

(A) A misconfigured home printer
(B) A Wi-Fi network impersonating a legitimate one to intercept the traffic of devices that join
(C) An email requesting password confirmation
(D) A program recording keystrokes

Question 19

What does both(4, 9) return?

PROCEDURE bigger(x, y)
{
    IF (x > y)
    {
        RETURN (x)
    }
    RETURN (y)
}

PROCEDURE both(a, b)
{
    RETURN (bigger(a, b) − bigger(1, 2))
}

(A) 2
(B) 9
(C) 5
(D) 7

Question 20

An online form saves partial progress every 30 seconds so that a browser crash loses little work. In fault-tolerance terms, the periodic saving is:

(A) A syntax checker
(B) An attack on the user's privacy
(C) Redundancy that lets the system recover from a failure
(D) A protocol violation

Question 21

The number 53 in binary is:

(A) 110101
(B) 101011
(C) 111000
(D) 110011

Question 22

A photo app offers an "enhance" feature that uploads images to remote servers for processing by powerful machines, returning results in seconds. The architecture described is:

(A) Sequential computing on the phone
(B) Distributed computing — the phone and remote servers divide the work
(C) A rogue access point
(D) Run-length encoding

Question 23

For which starting value of n does this loop run FOREVER?

REPEAT UNTIL (n = 12)
{
    n ← n + 3
}

(A) 3
(B) 6
(C) 9
(D) 10

Question 24

Which is an example of using abstraction to manage program complexity?

(A) Writing all code in one long sequence without procedures
(B) Copying the same ten lines wherever they're needed
(C) Naming a block of code validateEntry and calling it wherever validation is needed, hiding its details
(D) Avoiding comments to keep files small

Question 25

A dataset of app reviews includes each review's text, star rating, submission date, and reviewer's device model. A analyst filtering rating ≤ 2 then examining common words in the surviving text is doing what?

(A) Extracting information (patterns in negative reviews) from data
(B) Encrypting the reviews
(C) Introducing bias into the reviews
(D) Compressing the dataset

Question 26

What is displayed?

x ← 8
y ← 3
IF (x MOD y = 2)
{
    x ← x + y
}
IF (x > 10)
{
    y ← y * 2
}
DISPLAY (x + y)

(A) 11
(B) 14
(C) 13
(D) 17

Question 27

The main reason binary search cannot be used directly on the list ["pear", "apple", "fig", "mango"] is:

(A) Binary search works only on numbers
(B) The list is not sorted
(C) The list is too short
(D) Strings cannot be compared

Question 28

A company's hiring page is only navigable with a mouse, making it unusable for keyboard-only and screen-reader users. This design:

(A) Is required by open protocols
(B) Affects only a small number of users, so it is not a concern
(C) Excludes users with disabilities — an accessibility failure related to who was imagined and tested as "the user"
(D) Is a run-time error

Question 29

What is the value of result?

vals ← [5, 1, 8, 3]
result ← 0
FOR EACH v IN vals
{
    IF (v > result)
    {
        result ← v
    }
}
result ← result MOD 3

(A) 8
(B) 1
(C) 0
(D) 2

Question 30

A certificate authority's digital certificate allows a browser to trust that:

(A) A website's public key genuinely belongs to the site it claims to be
(B) The website contains no errors
(C) The user's password is strong
(D) Packets will arrive in order

Question 31

Two expressions produce the same value for every input: 3 * (n + 2) and:

(A) 3 * n + 2
(B) 3 * n + 6
(C) n + 6
(D) 3 * n * 2

Question 32

A team's simulation of checkout lines uses RANDOM(1, 4) minutes per customer. Run twice with the same starting conditions, the simulation produces different wait times. This variation:

(A) Means the simulation contains a logic error
(B) Should be eliminated before results are reported
(C) Proves simulations cannot model real systems
(D) Is intentional — randomness models real-world variability, and repeated runs reveal the range of outcomes

Question 33

word ← "STORAGE". The substring from position 2 to position 4 (inclusive) is:

(A) "TOR"
(B) "STO"
(C) "ORA"
(D) "TORA"

Question 34

Which change to a study-group app would MOST directly help close a digital-divide gap among its users?

(A) Adding more notification sounds
(B) Requiring the newest phone models
(C) Providing a low-bandwidth mode that works on slow connections and older devices
(D) Removing the offline mode

Question 35

What does this code display?

count ← 0
FOR EACH n IN [12, 5, 18, 9, 21]
{
    IF (n MOD 3 = 0)
    {
        count ← count + 1
    }
}
DISPLAY (count)

(A) 2
(B) 4
(C) 5
(D) 3

Question 36

A 16-pixel row alternates BWBWBWBWBWBWBWBW. Compared with storing raw pixels (1 bit each), run-length encoding this row with 5-bit pairs would:

(A) Cut the size in half
(B) Reduce the size by exactly one bit
(C) Increase the size — 16 runs of length 1 produce more encoding overhead than savings
(D) Be impossible

Question 37

What does p(3) display?

PROCEDURE q(n)
{
    RETURN (n * n − 1)
}

PROCEDURE p(n)
{
    DISPLAY (q(n) + q(n + 1))
}

(A) 23
(B) 15
(C) 8
(D) 17

Question 38

Which correctly orders the events when a user requests a web page?

(A) TCP reassembles → IP addresses → DNS translates
(B) DNS translates the name → IP routes the packets → TCP delivers them complete and in order
(C) IP translates the name → DNS routes → TCP displays
(D) TCP translates → DNS delivers → IP reorders

Question 39

A team compares two implementations of the same specification. Implementation X checks each of n entries once. Implementation Y checks every possible pair of entries. As n grows large:

(A) X and Y take identical time
(B) Y becomes unreasonable while X stays reasonable
(C) X is slower than Y
(D) Both remain reasonable — pairwise checking is polynomial (n²), though slower than X's linear approach

Question 40

A journalism nonprofit wants its investigative database available to every researcher for free rather than behind a paywall. The publishing model it wants is:

(A) All rights reserved
(B) Trade secret
(C) Open access
(D) Keylogging

Question 41

What is displayed?

outer ← 0
REPEAT 3 TIMES
{
    inner ← 0
    REPEAT 2 TIMES
    {
        inner ← inner + 1
    }
    outer ← outer + inner
}
DISPLAY (outer)

(A) 5
(B) 6
(C) 3
(D) 2

Question 42

A voice assistant mishears commands from users in noisy households far more often than in quiet ones, because its training recordings were made in quiet studios. The mismatch is an example of:

(A) Training conditions that don't represent real use conditions — a bias/representativeness gap
(B) An overflow error
(C) Users speaking incorrectly
(D) Fault tolerance

Question 43

Which situation involves PII being exposed through aggregation rather than through any single disclosure?

(A) A database of full names and passwords leaks
(B) A user posts their own phone number publicly
(C) A site publishes a member's home address
(D) Separate posts of a jogger's route map, workplace tag, and schedule are combined to determine where she will be alone tomorrow

Question 44

What does mix() return?

PROCEDURE mix()
{
    L ← [4, 7, 1]
    INSERT(L, 2, 9)
    RETURN (L[2] + L[3])
}

(A) 8
(B) 16
(C) 11
(D) 13

Question 45

The Internet Engineering Task Force publishes protocol standards openly, and any manufacturer may implement them without permission or fees. This practice most directly enables:

(A) Perfect security for all devices
(B) Central control of network growth
(C) Interoperability between devices and networks from any vendor, supporting the Internet's growth
(D) Faster processors

Question 46

A program must run 6 independent database queries taking 10, 20, 30, 40, 50, and 60 seconds, plus 15 seconds of sequential report assembly afterward. With two processors for the queries, the BEST achievable total time is:

(A) 225 seconds
(B) 75 seconds
(C) 110 seconds
(D) 125 seconds

Question 47

Which test input set BEST tests a procedure that charges $2 per pound for packages up to 10 pounds and a flat $25 above 10 pounds?

(A) Weights 9.5, 10, and 10.5 pounds
(B) Weights 1, 2, and 3 pounds
(C) Weights 50, 100, 150 pounds
(D) One weight of 5 pounds

Question 48

A streaming site tracks every video a user watches, then recommends similar content. The recommendation feature and the tracking it requires illustrate:

(A) Lossless compression
(B) The dual nature of personalization — convenience built from behavioral data collection users may not fully realize is occurring
(C) A syntax error in the site
(D) Fault tolerance

Question 49

What is displayed?

a ← 2
b ← a + 2
a ← b * a
b ← a MOD b
DISPLAY (a)
DISPLAY (b)

(A) 8 then 4
(B) 4 then 8
(C) 8 then 0
(D) 6 then 2

Question 50

Sequential search examines an unsorted 10,000-entry list. Binary search examines a SORTED 10,000-entry list. Worst-case examinations, respectively, are approximately:

(A) 10,000 and 14
(B) 14 and 10,000
(C) 10,000 and 5,000
(D) 100 and 10

Question 51

An app's terms allow it to sell users' location history to advertisers. Users tapped "agree" without reading. The CED's framing of this situation emphasizes:

(A) That tapping agree makes all concerns disappear
(B) That location data has no value
(C) That the app contains a logic error
(D) That personal data has commercial value and flows to third parties in ways users often don't understand or meaningfully consent to

Question 52

What is displayed?

flag ← false
FOR EACH n IN [4, 8, 11, 6]
{
    IF (n MOD 2 = 1)
    {
        flag ← true
    }
}
IF (flag)
{
    DISPLAY ("found")
}
ELSE
{
    DISPLAY ("none")
}

(A) none
(B) found none
(C) found
(D) 11

Question 53

Which pseudocode segments are equivalent — producing identical behavior for every value of x? Segment I: IF (x > 5) { y ← 1 } ELSE { y ← 0 } Segment II: y ← 0 then IF (x > 5) { y ← 1 }

(A) Only when x > 5
(B) Always — both set y to 1 exactly when x > 5 and 0 otherwise
(C) Never
(D) Only when x = 5

Question 54

A hospital's patient records and a fitness app's step data are merged (with consent) by patient ID for a study. Researchers can now investigate questions neither dataset supported alone. This capability is an example of:

(A) Combining data sources to extract new information — with heightened privacy stakes
(B) A rogue access point
(C) Data compression
(D) Procedural abstraction

Question 55

In this code, the programmer intended to display the average. What is actually displayed for vals ← [6, 10, 8]?

total ← 0
FOR EACH v IN vals
{
    total ← total + v
    avg ← total / LENGTH(vals)
    DISPLAY (avg)
}

(A) 8 once
(B) 24 once
(C) 8 three times
(D) 2, then 5.33, then 8 — the "average" prints every iteration, mostly wrong

Question 56

A checkout program stores prices in cents as integers (e.g., $4.99 → 499) rather than as decimal dollar amounts. The MOST likely motivation is:

(A) Integers make the display prettier
(B) Avoiding roundoff errors that accumulate when many decimal amounts are added
(C) Cents compress better
(D) Prices cannot exceed one dollar otherwise

Question 57

Which practice BEST reflects responsible development for a public-facing app?

(A) Testing only on the development team's own devices
(B) Assuming users will read documentation before touching anything
(C) Testing with users of varying abilities, devices, and connection speeds before wide release
(D) Releasing quickly and letting crash reports find the bugs

Questions 58–62: Reading Passage

NoiseNet is a program run by a coastal city to manage nighttime noise complaints. Residents install a small outdoor sensor (provided free) that measures sound levels every 10 seconds. Sensors do not record audio — only decibel readings, timestamps, and the sensor's registered address. Readings upload continuously to city servers. When a neighborhood's readings exceed legal limits repeatedly, the system flags the area for enforcement follow-up, and a public map displays average nighttime noise by district (not by address). Sensor distribution began through an online sign-up that filled within days; city data shows participating households cluster in districts with high home-ownership rates. An audit found sensor placement (near a window vs. behind a hedge) causes readings to vary by up to 8 decibels between adjacent homes.

Question 58

NoiseNet's primary purpose is to:

(A) Record conversations in noisy neighborhoods
(B) Provide the city evidence-based noise enforcement and public noise information
(C) Sell sensors to residents
(D) Replace all human noise inspectors

Question 59

Which data do the city's servers receive from each sensor?

(A) Audio recordings and addresses
(B) Only district-level averages
(C) The residents' complaints
(D) Decibel readings, timestamps, and the sensor's registered address

Question 60

The clustering of sensors in high home-ownership districts means enforcement flags may:

(A) Reflect where sensors are, not where noise is worst — a participation/collection bias that could skew enforcement toward covered districts
(B) Be perfectly accurate citywide
(C) Violate TCP
(D) Prove renters make more noise

Question 61

The audit's placement finding (readings vary up to 8 dB by sensor position) most directly threatens:

(A) The public map's color scheme
(B) The city's servers
(C) The comparability of readings between homes — measured differences may reflect placement, not actual noise
(D) The sensors' power supply

Question 62

Which design choice in NoiseNet most directly limits privacy risk?

(A) Uploading readings continuously
(B) Sensors that measure only decibel levels — no audio — and a public map aggregated by district rather than address
(C) The free sensor program
(D) Flagging neighborhoods for enforcement

Questions 63–70: Multiple-Select — Select TWO answers for each. Both must be correct to earn the point.

Question 63

Which statements about the following code are true? (Select two.)

i ← 1
REPEAT UNTIL (i > 4)
{
    DISPLAY (i * i)
    i ← i + 1
}

(A) It displays five values
(B) It displays 1, 4, 9, 16
(C) The final value of i is 4
(D) The loop body runs exactly 4 times

Question 64

Which statements about encryption are true? *(Select two.)

(A) In public-key encryption, the public key must be kept secret
(B) Symmetric encryption is impossible to use safely
(C) Public-key encryption lets parties communicate securely without previously sharing a secret key
(D) A message encrypted with a recipient's public key is decrypted with that recipient's private key

Question 65

A social platform's recommendation algorithm increases engagement while also amplifying sensational misinformation. Which responses reflect the CED's analysis? *(Select two.)

(A) The amplification is a harmful effect that can coexist with the engagement benefit
(B) Because engagement was the goal, the misinformation amplification is not the platform's effect
(C) The platform's code must contain a run-time error
(D) The scale of the platform intensifies the harm compared with a small forum

Question 66

Which are true of the AP pseudocode's list operations? *(Select two.)

(A) LENGTH(L) returns the index of the last element
(B) L[0] refers to the first element
(C) APPEND(L, x) always places x at index LENGTH(L) after the operation
(D) REMOVE(L, i) decreases the indexes of all elements that were after position i by 1

Question 67

A procedure must return true when EVERY value in a list is positive, and false otherwise. Which implementations are correct? (Select two.) Implementation I:

result ← true
FOR EACH v IN list
{
    IF (v ≤ 0) { result ← false }
}
RETURN (result)

Implementation II:

FOR EACH v IN list
{
    IF (v ≤ 0) { RETURN (false) }
}
RETURN (true)

Implementation III:

result ← false
FOR EACH v IN list
{
    IF (v > 0) { result ← true }
}
RETURN (result)

(A) Implementation III
(B) None of the three implementations is correct
(C) Implementation I
(D) Implementation II

Question 68

Which statements describe genuine trade-offs? *(Select two.)

(A) Lossy compression: much smaller files, but the original cannot be recovered
(B) Redundant network links: greater fault tolerance, but higher hardware cost and complexity
(C) Binary search: works on any list with no requirements whatsoever
(D) Open protocols: fast growth, but require every device to be made by one vendor

Question 69

Which scenarios describe a computing innovation's data being repurposed beyond its original collection purpose? *(Select two.)

(A) A navigation app's driver-speed data being sold to set individual insurance rates
(B) A calculator app computing the numbers a user enters
(C) A smart-TV's viewing history being used by data brokers to build political profiles
(D) A game displaying its own high-score table

Question 70

Which statements about testing are consistent with the CED? *(Select two.)

(A) A program that passes every typical-input test is guaranteed correct
(B) Test cases should include boundary and extreme inputs, where errors concentrate
(C) Testing each component as it is developed helps locate errors early
(D) Testing is unnecessary when a program compiles without complaint

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Show answer key & explanations

Mock Exam 2 — Answer Key & Review Guide

Scoring: 1 point per question (multi-select questions require BOTH correct answers). Total: 70 points.

Questions 1–35

Q	Ans	Why (and why not)	Review
1	D	10 MOD 4 = 2; 2 × 2 = 4. (B) squares before the MOD	L7
2	C	Requirements describe intended behavior, validated later by testing	L2
3	A	2⁷ − 1 = 127; (B) counts the values, not the max	L3
4	B	n = 6, 4, 2 accumulate (6+4+2 = 12); at n = 0 the condition 0 ≤ 0 stops the loop	L11
5	D	Scan = data in; chime and database write = program outputs	L1
6	A	A shared field is the join requirement	L6
7	C	[7,2,9,4] → remove idx 3 → [7,2,4] → insert 5 at 3 → [7,2,5,4] → append → [7,2,5,4,2]	L8
8	D	Uniform-rainfall assumption erases the local variation floods depend on — unreliable exactly where it matters	L16
9	B	Exclusive endpoints = strict inequalities joined by AND. (A) is inclusive; (D)'s inner AND is never true, making NOT always true	L9
10	A	Filter defines the subset; count the survivors	L6
11	C	Prepending reverses: "x" → "yx" → "zyx"	L11
12	D	First IF false (3 < 7); second IF true → b = 7 − 3 = 4	L10
13	B	Unreasonable = exponential or worse; (D) n² is polynomial = reasonable	L13
14	A	Sums span 6..14 → 14 − 6 + 1 = 9 distinct values; (B) counts ordered pairs	L15
15	C	(1,1)N: 3 forward → (4,1); right → E; 3 forward → (4,4); right → S. Top-right, facing south	L10, L11
16	A	Bias lives in data/assumptions, not in whether the code runs correctly	L21
17	D	total = 2+4+6 = 12; i ends at 4 (incremented after last use); 12 + 4 = 16 — the off-by-one counter question	L11, L7
18	B	Impersonating network intercepting joiners' traffic = rogue AP; (C) is phishing; (D) keylogging	L23
19	D	bigger(4,9) = 9; bigger(1,2) = 2; 9 − 2 = 7. Two procedures, resolved inside-out	L14
20	C	A saved copy = redundancy; recovery despite failure = fault tolerance applied to software	L18
21	A	53 = 32+16+4+1 → 110101. Verify by adding back	L3
22	B	Phone + remote servers dividing work across machines = distributed	L19
23	D	From 10: 13, 16, ... steps over 12, never equal → infinite. From 3/6/9, the +3 chain lands exactly on 12	L11
24	C	Named procedure hiding details, reused by call = procedural abstraction	L14
25	A	Filter + pattern examination = extracting information from data	L5, L6
26	D	8 MOD 3 = 2 → x = 11; 11 > 10 → y = 6; 11 + 6 = 17. Two independent IFs — both get evaluated	L10
27	B	Unsorted = binary search invalid. Strings sort fine (alphabetically) — (A)/(D) are false	L13
28	C	Excluded-by-design users = accessibility failure; "small number" (B) is both false and beside the point	L21
29	D	Max-finder yields 8 (init 0 is safe here — all values positive); 8 MOD 3 = 2. Post-loop step is half the question	L12, L7
30	A	The CA binds identity to public key — that's the entire trust service	L23
31	B	Distribute: 3(n + 2) = 3n + 6. Test n = 1: 9 = 9 ✓; (A) gives 5 ✗	L7
32	D	Randomness is the model of real variability; run-to-run variation is the feature, and many runs map the range	L16, L15
33	A	S(1) T(2) O(3) R(4): positions 2–4 = "TOR"	L8
34	C	Low-bandwidth mode meets users on the far side of the divide; (B) widens it	L21
35	B	Divisible by 3: 12, 18, 9, 21 → 4. (D) misses one — check all five	L12, L7

Questions 36–57

Q	Ans	Why (and why not)	Review
36	C	16 runs × 5 bits = 80 bits vs. 16 raw — RLE loses on redundancy-free data	L4
37	A	q(3) = 8; q(4) = 15; 8 + 15 = 23	L14
38	B	Translate (DNS) → route (IP) → deliver complete/ordered (TCP)	L17
39	D	Pairwise = n² = polynomial = still reasonable; (B) is the "sounds explosive" trap	L13
40	C	Paywall-free research = open access, by name	L22
41	B	inner rebuilds to 2 each pass; outer = 2, 4, 6	L11
42	A	Training conditions ≠ deployment conditions — the representativeness gap	L21
43	D	Three innocuous posts combine into a location-and-time exposure — aggregation, not any single leak	L23
44	B	[4,7,1] → INSERT at 2 → [4,9,7,1]; L[2] + L[3] = 9 + 7 = 16	L8
45	C	Open standards → any-vendor interoperability → growth	L17
46	D	Balanced split of {10..60}: best is 110 vs 100 (e.g., 60+50 / 40+30+20+10) → max 110, + 15 sequential = 125. (C) forgets the sequential step; (B) assumes six processors	L19
47	A	The rule changes at 10 pounds; 9.5/10/10.5 straddle the boundary	L2
48	B	Personalization's bargain: convenience for behavioral data — both halves named	L20, L23
49	C	a = 8 (4×2), then b = 8 MOD 4 = 0. Displays 8 then 0	L7
50	A	Linear worst case = n = 10,000; binary ≈ 14 (2¹⁴ = 16,384)	L13
51	D	Data's commercial value + consent users don't meaningfully give — the CED's privacy economy claim	L23
52	C	11 is odd → flag set → "found." The existence-check silhouette	L12
53	B	Both produce y = 1 iff x > 5, else 0 — same behavior, different construction; equivalence is behavioral	L9, L12
54	A	Combining sources → new information + heightened privacy stakes — both clauses matter	L6, L23
55	D	The DISPLAY sits inside the loop: prints total/3 every pass (2, 5.33, 8). Misplaced-statement bugs print early and wrong	L12
56	B	Integer cents sidestep accumulating decimal roundoff — Lesson 3's roundoff, engineered around	L3
57	C	Test across the real range of users/devices/connections — responsible development in one sentence	L21, L2

Questions 58–62 (Passage)

Q	Ans	Why (and why not)	Review
58	B	Evidence-based enforcement + public information — both stated. (A) contradicts "no audio"; (D) overreaches	L24
59	D	Listed verbatim: decibels, timestamps, registered address. (B) describes what the public sees, not what servers receive	L24
60	A	Sensor placement follows sign-up patterns → coverage bias → enforcement skew. The passage hands you the mechanism	L21, L5
61	C	An 8 dB placement artifact swamps between-home comparisons — measurement validity, not privacy or power	L5, L16
62	B	No audio + district-level aggregation = privacy-by-design, twice over	L23, L24

Questions 63–70 (Multi-Select — both required)

Q	Ans	Why (and why not)	Review
63	B, D	i = 1,2,3,4 each fail `> 4` → 4 runs displaying 1, 4, 9, 16; i finishes at 5, not 4 — (C) is the off-by-one	L11
64	C, D	No-prior-secret communication; public-encrypts/private-decrypts. (A) inverts the key rule	L23
65	A, D	Dual effects + scale amplification. (B) denies effects-beyond-purpose; (C) confuses outcomes with errors	L20
66	C, D	APPEND lands at the new last index; REMOVE shifts later elements left. (A): LENGTH returns the count (numerically equal to the last index, but it returns the length — the safest true statements are C and D); (B) is 0-indexing	L8
67	C, D	I (flag, no early exit) and II (early-exit RETURN) both compute "all positive." III computes "at least one positive" — the existence check, not the universal	L12, L14
68	A, B	Real trade-offs: shrink-vs-recovery; resilience-vs-cost. (C) erases binary search's sorted prerequisite; (D) inverts openness	L4, L18, L13
69	A, C	Collected-for-navigation → insurance pricing; collected-for-viewing → political profiling: both are repurposing. (B)/(D) use data exactly as collected	L23, L20
70	B, C	Boundary-inclusive test suites; test-as-you-build. (A)/(D) are the overconfidence anti-patterns	L2

Scoring Worksheet

1. Raw score: ______ / 70

2. Compare with Mock 1: __ / 70 → gains concentrated in which Big Ideas? ____

3. Estimated AP band (same method and caveats as Mock 1 — these are study-prioritization estimates, not predictions):

Section I raw	With a solid PT	With a weaker PT
55–70	5 likely	4–5
45–54	4 likely	3–4
35–44	3 likely	3
27–34	2–3	2
below 27	2	1–2

4. Diagnosis by Big Idea:

Big Idea	Questions	Missed	If 3+ missed, reread
CRD	2, 5, 24, 47, 55, 57, 70	___ / 7	L1–L2, L14
DAT	3, 6, 8, 10, 21, 25, 36, 54, 56, 66	___ / 10	L3–L6
AAP	1, 4, 7, 9, 11, 12, 13, 14, 15, 17, 19, 23, 26, 27, 29, 31, 32, 33, 35, 37, 41, 44, 49, 50, 52, 53, 63, 67	___ / 28	L7–L16
CSN	20, 22, 38, 39, 45, 46, 64	___ / 7	L17–L19
IOC	16, 18, 28, 30, 34, 40, 42, 43, 48, 51, 58–62, 65, 68*, 69	___ / 18	L20–L24

Some questions span Big Ideas; the totals differ slightly from official weightings because integrated questions are the point of a final mock.

Appendix: Written-Response Practice (Section II — second rehearsal)

This time, the sample program is closer to real PT scale. Read the PPR, answer all four prompts in writing, THEN compare with the models. Finally — and this is the assignment — answer all four about your own PT without looking at anything but your own PPR.

Sample program: "LapLog" (tracks swim-practice lap times and reports progress)

PPR — list creation and use:

lapTimes ← []
...
APPEND(lapTimes, newTime)        ← each recorded lap joins the list

PPR — procedure and call:

PROCEDURE bestAverage(times, n)
{
    IF (LENGTH(times) < n)
    {
        RETURN (-1)
    }
    best ← -1
    i ← 1
    REPEAT UNTIL (i + n − 1 > LENGTH(times))
    {
        sum ← 0
        j ← i
        REPEAT n TIMES
        {
            sum ← sum + times[j]
            j ← j + 1
        }
        IF (best = -1 OR sum < best)
        {
            best ← sum
        }
        i ← i + 1
    }
    RETURN (best / n)
}

fastest3 ← bestAverage(lapTimes, 3)     ← the call
DISPLAY (fastest3)

Prompts and models

WR 1 (Design, Function, Purpose): Purpose: help a swimmer see her best sustained performance, not just her single fastest lap. Function/interaction: the swimmer records each lap time; on request, the program reports the fastest average of any n consecutive laps (fastest3 = best 3-lap stretch). Input: lap times; output: the best n-lap average, or −1 when fewer than n laps exist.

WR 2(a) (Algorithm Development): The procedure slides a window of n consecutive laps across the list (outer REPEAT UNTIL moves the start index i; inner REPEAT n TIMES sums the window). Selection (IF (best = -1 OR sum < best)) keeps the smallest window sum seen so far — the best = -1 clause accepts the first window unconditionally, the min-finder's honest-initialization rule. Divided by n at the end, the smallest sum becomes the fastest average. The guard IF (LENGTH(times) < n) handles the impossible case up front.

WR 2(b) (Errors and Testing): Test: times = [30, 28, 26, 29], n = 3. Windows: 30+28+26 = 84 and 28+26+29 = 83 → best = 83 → returns 27.67. A common implementation error — initializing best ← 0 without the -1 first-window clause — would make every real sum "worse" than best and return 0; this test exposes it because the expected answer is 27.67, not 0. Boundary test: 2 laps with n = 3 must return −1, not crash.

WR 2(c) (Data and Procedural Abstraction): lapTimes holds every recorded lap under one name, so the window algorithm works identically for a week or a season of data — the code never changes as the list grows. bestAverage abstracts the whole analysis behind one call: the main program asks a question (bestAverage(lapTimes, 3)) without containing any of the window logic, and improving the algorithm later would require no changes at the call site.

After both mocks: your two raw scores bracket your current Section I range. Spend remaining study time on (1) whichever Big Idea cost you the most points across both mocks and (2) written-response rehearsal with your own PPR — Section II is 30% of the score and 100% preparable. Good luck — go earn the 5.

Score summary

Your running multiple-choice score appears in the bar below. Self-score the free-response section with the rubrics in the answer key, then use the diagnostic table to target review.

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End of course