English Questions
Questions 1-3
The Great Barrier Reef is the world's largest coral reef system, it stretches over 2,300 kilometers along the northeast coast of Australia.
Which of the following alternatives to the underlined portion would be grammatically correct?
, it
; it
, and it being that it
, therefore, it
Explanation
The correct answer is B) ; it. The original sentence contains a comma splice — two independent clauses joined by only a comma. A semicolon correctly links two closely related independent clauses. Choice A repeats the comma splice error. Choice C is unnecessarily wordy and awkward. Choice D is also a comma splice ("therefore" is a conjunctive adverb, not a coordinating conjunction, so it needs a semicolon before it or a period).
The museum's new exhibit, however, failed to attract the expected number of visitors during its opening weekend.
Which of the following alternatives to the underlined portion would NOT be acceptable?
nevertheless,
on the other hand,
furthermore,
unfortunately,
Explanation
The correct answer is C) furthermore. The word "however" signals a contrast or unexpected outcome. "Nevertheless" (A) and "on the other hand" (B) also signal contrast and are acceptable substitutes. "Unfortunately" (D) conveys a negative outcome, which fits the context of disappointing attendance. "Furthermore" (C) signals addition, not contrast — it would mean the museum's failure is being added to a list of positive qualities, which contradicts the sentence's meaning. This is a classic ACT "NOT acceptable" format.
The collection of rare manuscripts from the university's archives were displayed at the annual academic conference.
Which choice correctly replaces the underlined portion?
were
was
have been
are being
Explanation
The correct answer is B) was. The subject of the sentence is "collection" (singular), not "manuscripts" or "archives." The prepositional phrases "of rare manuscripts" and "from the university's archives" are interrupters that do not change the subject. A singular subject requires a singular verb: "was displayed." Choices C and D change the tense, which is not supported by context. This is one of the most common ACT grammar traps.
Math Questions
Questions 4-6
If 5(x - 2) + 3 = 2x + 8, what is the value of x?
x = 3
x = 5
x = 7
x = 15
Explanation
Distribute and solve step by step:
- 5(x - 2) + 3 = 2x + 8
- 5x - 10 + 3 = 2x + 8
- 5x - 7 = 2x + 8
- 3x = 15
- x = 5
Check: 5(5 - 2) + 3 = 5(3) + 3 = 15 + 3 = 18. And 2(5) + 8 = 10 + 8 = 18. Both sides equal 18, confirming B) x = 5.
A triangle has a base of 14 cm and a height of 9 cm. What is the area of the triangle, in square centimeters?
63
126
46
23
Explanation
The area of a triangle is A = (1/2) × base × height.
A = (1/2) × 14 × 9 = (1/2) × 126 = 63 cm².
Choice B (126) is the result of forgetting to multiply by 1/2. Choices C and D are incorrect calculations. The correct answer is A) 63.
A student received the following scores on five math quizzes: 82, 91, 76, 88, and 93. What is the mean (average) of these scores?
82
86
88
91
Explanation
The mean is the sum of all values divided by the number of values.
Sum = 82 + 91 + 76 + 88 + 93 = 430
Mean = 430 ÷ 5 = 86
Choice C (88) is the median (middle value when sorted). Choice D (91) is the second-highest score. The correct answer is B) 86.
Reading Questions
Questions 7-8
Urban beekeeping has grown dramatically in the past decade. Cities like New York, London, and Tokyo now host thousands of rooftop hives managed by hobbyists and commercial operators alike. Proponents argue that urban bees improve pollination of city gardens and green spaces, contributing to local food production and biodiversity. Critics, however, warn that the rapid increase in managed honeybee colonies may actually harm native bee populations by increasing competition for limited floral resources. Research published in 2022 found that in areas with high densities of managed hives, native solitary bee populations declined by up to 20%.
Which of the following best states the main idea of the passage?
Urban beekeeping is universally beneficial for city ecosystems.
The growth of urban beekeeping has both benefits and drawbacks for urban ecosystems.
Native bee populations are declining because of climate change.
Commercial beekeeping operations should be banned in major cities.
Explanation
The correct answer is B). The passage presents both the benefits of urban beekeeping (improved pollination, biodiversity) and the concerns (competition with native bees, a 20% decline in native populations). This balanced treatment means the main idea is about both sides. Choice A ignores the criticism. Choice C introduces a cause (climate change) not mentioned in the passage. Choice D states an opinion not expressed by the passage.
Urban beekeeping has grown dramatically in the past decade. Cities like New York, London, and Tokyo now host thousands of rooftop hives managed by hobbyists and commercial operators alike. Proponents argue that urban bees improve pollination of city gardens and green spaces, contributing to local food production and biodiversity. Critics, however, warn that the rapid increase in managed honeybee colonies may actually harm native bee populations by increasing competition for limited floral resources. Research published in 2022 found that in areas with high densities of managed hives, native solitary bee populations declined by up to 20%.
According to the passage, by what percentage did native solitary bee populations decline in areas with high densities of managed hives?
10%
15%
20%
25%
Explanation
The correct answer is C) 20%. The passage explicitly states that research found native solitary bee populations "declined by up to 20%." This is a straightforward detail retrieval question — the answer is stated directly in the text. Always go back to the passage to verify specific numbers rather than relying on memory.
Science Questions
Questions 9-10
A researcher measured the growth rate of bacteria (in colonies per mL) at different temperatures. The results are shown in the table below.
| Temperature (°C) | Colonies per mL (after 24 hr) |
|---|---|
| 10 | 50 |
| 20 | 200 |
| 30 | 800 |
| 37 | 1,500 |
| 45 | 600 |
| 55 | 100 |
Based on the data in the table, at what temperature was the bacterial growth rate highest?
20°C
30°C
37°C
45°C
Explanation
The correct answer is C) 37°C. Looking at the "Colonies per mL" column, the highest value is 1,500, which corresponds to a temperature of 37°C. This makes biological sense — 37°C is the optimal growth temperature for many common bacteria (it is human body temperature). Growth decreases at both lower and higher temperatures, showing a classic bell-shaped relationship between temperature and bacterial growth.
Experiment: A student wanted to determine how the amount of sunlight affects the growth of bean plants. She set up four groups of identical bean seedlings. Each group was placed in a growth chamber with a different amount of daily light exposure: 4 hours, 8 hours, 12 hours, and 16 hours. All groups received the same amount of water, the same type of soil, and were kept at the same temperature (22°C). After 30 days, the student measured the average height of the plants in each group.
In this experiment, what is the independent variable?
The average height of the bean plants after 30 days
The amount of daily light exposure
The type of soil used
The temperature of the growth chamber
Explanation
The correct answer is B) The amount of daily light exposure. The independent variable is the factor the experimenter intentionally changes — here, the student varied the hours of light (4, 8, 12, 16). Choice A (plant height) is the dependent variable — it is what was measured as a result. Choices C (soil type) and D (temperature) are controlled variables — they were deliberately kept constant across all groups to ensure a fair comparison. Distinguishing between independent, dependent, and controlled variables is one of the most tested skills in the ACT Science section.
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