Use this diagnostic to find which Unit 5 topics to revisit: two questions for each topic.
These are original Marlbridge practice questions, not past exam questions, with fictional scenarios. The diagnostic is not calibrated and gives no predicted score. Answers should be balanced and non-political.
How to take it. Allow 30 minutes and answer everything before opening any answer. No calculator.
Question 1 (multiple choice · 5.1)
A fictional app that finds the quickest driving route sends many cars along a quiet street. Drivers save time, while residents of the street face more noise. Which statement is correct?
- (A) The effect is beneficial for some people and harmful for others.
- (B) The effect is harmful for everyone.
- (C) The effect is beneficial for everyone.
- (D) The developers must have intended the noise.
Answer and explanation
Answer: (A). One innovation can have effects that different people view differently.
- (B) and (C) ignore one of the groups.
- (D) nothing suggests intention.
If you missed this: Topic 5.1 study guide.
Question 2 (multiple choice · 5.1)
A fictional photo-sharing app built for friends is used by a school to display class events, which pupils enjoy. This is best described as
- (A) an innovation used beyond its original purpose, here with a beneficial effect
- (B) a syntax error
- (C) a lossless compression
- (D) a certificate authority
Answer and explanation
Answer: (A).
- (B), (C) and (D) are unrelated.
If you missed this: Topic 5.1 study guide.
Question 3 (multiple choice · 5.2)
Which best describes the digital divide?
- (A) Differing access to computing devices and the Internet, based on socioeconomic, geographic or demographic characteristics
- (B) The difference between two operating systems
- (C) A program split into modules
- (D) Dividing a file into packets
Answer and explanation
Answer: (A).
- (B), (C) and (D) are unrelated meanings.
If you missed this: Topic 5.2 study guide.
Question 4 (multiple choice · 5.2)
In a fictional district, 45 of 150 homes have no Internet connection. What percentage of homes have no connection?
- (A) 3%
- (B) 30%
- (C) 70%
- (D) 45%
Answer and explanation
Answer: (B). 45 ÷ 150 = 0.30, or 30%.
- (A) divides 150 by 45 incorrectly.
- (C) is the percentage that do have a connection (105 ÷ 150).
- (D) uses the count as a percentage.
If you missed this: Topic 5.2 study guide.
Question 5 (multiple choice · 5.3)
A fictional system is right on 54 of 60 tests for Group P and 12 of 20 tests for Group Q. What are the accuracies for P and Q?
- (A) 90% and 60%
- (B) 54% and 12%
- (C) 60% and 90%
- (D) 75% and 75%
Answer and explanation
Answer: (A). 54 ÷ 60 = 0.90; 12 ÷ 20 = 0.60.
- (B) uses counts as percentages.
- (C) swaps the groups.
- (D) would mean both groups are equally accurate; the two accuracies are different (the overall figure is 66 ÷ 80 = 82.5%).
If you missed this: Topic 5.3 study guide.
Question 6 (multiple choice, select two · 5.3)
Which two actions could help reduce bias in a computing innovation?
- (A) Testing results separately for different groups
- (B) Using training data that represent a wider range of people
- (C) Reporting only the overall accuracy
- (D) Assuming the program is fair because it uses code
Answer and explanation
Answer: (A) and (B).
- (C) hides group differences.
- (D) code can carry bias from data and design.
If you missed this: Topic 5.3 study guide.
Question 7 (multiple choice · 5.4)
Volunteers use their own phones to record bird sightings, which scientists then combine to map bird populations. This is an example of
- (A) citizen science
- (B) overflow
- (C) lossy compression
- (D) fault tolerance
Answer and explanation
Answer: (A).
- (B), (C) and (D) are unrelated.
If you missed this: Topic 5.4 study guide.
Question 8 (constructed response · 5.4)
A fictional app gathers 500 reports about broken streetlights: 350 from the city centre, 100 from the suburbs and 50 from rural areas. The shares of the population in those areas are 40%, 35% and 25%. (a) Calculate each area’s share of the reports. (b) Say what the comparison suggests. (3 points)
Answer and explanation
Suggested Marlbridge rubric (3 points).
| Point | Award when the response… |
|---|---|
| 1 | gives the shares: 70%, 20% and 10% |
| 2 | says the centre is over-represented and rural areas under-represented compared with population |
| 3 | says the data may not show where lights are really broken (or suggests checking rural areas directly) |
Sample response. (a) 350 ÷ 500 = 70%, 100 ÷ 500 = 20%, 50 ÷ 500 = 10%. (b) The centre has 70% of the reports for 40% of the people, while rural areas have 10% for 25% of the people, so rural broken lights may be under-reported and should be checked.
If you missed this: Topic 5.4 study guide.
Question 9 (multiple choice · 5.5)
A student includes a paragraph from an article in their report, with the author’s name and the article’s title, and the article’s licence allows reuse with credit. Which statement is correct?
- (A) The student has used the work legally by following the licence and citing the author.
- (B) The student has committed plagiarism.
- (C) The licence is not valid.
- (D) Citing is not needed when a licence allows reuse.
Answer and explanation
Answer: (A). Permission (the licence) and credit (the citation) are both present.
- (B) plagiarism is use without permission presented as one’s own.
- (C) nothing suggests that.
- (D) material by others should always be cited.
If you missed this: Topic 5.5 study guide.
Question 10 (multiple choice · 5.5)
Which statement correctly describes open source software?
- (A) Programs made freely available that may be redistributed and modified
- (B) Research articles free of restrictions on access
- (C) Programs that no one may copy
- (D) Passwords that everyone knows
Answer and explanation
Answer: (A).
- (B) describes open access.
- (C) and (D) are not open source.
If you missed this: Topic 5.5 study guide.
Question 11 (multiple choice · 5.6)
A user unlocks a laptop with a fingerprint and a PIN. Which categories of evidence are used?
- (A) Inherence and knowledge
- (B) Possession and inherence
- (C) Knowledge only
- (D) Possession only
Answer and explanation
Answer: (A). The fingerprint is something you are (inherence) and the PIN is something you know (knowledge).
- (B) no object (possession) is used.
- (C) and (D) leave out a category in use.
If you missed this: Topic 5.6 study guide.
Question 12 (constructed response · 5.6)
A fictional employee gets an email, apparently from the company’s IT department, asking them to click a link and type their password to avoid an account lock. (a) Name the threat. (b) Explain one thing the employee should do. (c) Explain how multifactor authentication would limit the damage if the password were typed in. (3 points)
Answer and explanation
Suggested Marlbridge rubric (3 points).
| Point | Award when the response… |
|---|---|
| 1 | names phishing |
| 2 | gives an action (do not click; contact IT by a known route; report the email) |
| 3 | explains that a second category of evidence (such as a code on the employee’s phone) would still be needed, so the stolen password alone is not enough |
Sample response. (a) Phishing. (b) Do not click the link; contact IT using a known phone number or address and report the email. (c) With MFA an attacker would also need the code sent to the employee’s phone, so the password alone would not give access.
If you missed this: Topic 5.6 study guide.
What next?
For each question you missed, read the study guide linked in its answer. If you missed two or more in one topic, work through that topic’s practice questions. When you are ready, try the Unit 5 mixed review.