Free ACT Science: Conflicting Viewpoints Questions and Answers 2

Question 1

Scientist 1 argues that the observed acceleration in cosmic expansion is caused by dark energy — a repulsive force embedded in the fabric of space. Scientist 2 argues it results from a massive cosmic void through which our galaxy happens to be moving. The discovery that the acceleration rate is identical in all directions would most support:

Accepted Answer

Scientist 1, because dark energy acts uniformly in all directions throughout space

Answer

Dark energy is theorized to be a property of space itself — it should act uniformly in every direction. A cosmic void would create directional variation (stronger effect toward the void's center). Uniform acceleration supports Scientist 1.

Question 2

Two ecologists disagree about wolf reintroduction in Yellowstone. Ecologist A says wolves restored the ecosystem by reducing overgrazing by elk. Ecologist B says river channel changes attributed to wolves were actually caused by climate shifts and rainfall changes. Which evidence would most strengthen Ecologist B's position?

Accepted Answer

Records showing that river channel changes began before wolf reintroduction

Answer

If river changes preceded wolf reintroduction, they cannot be caused by the wolves — this directly supports Ecologist B's argument that the changes had a different cause (climate/rainfall).

Question 3

Student 1 argues that the Moon formed from debris ejected when a Mars-sized body struck early Earth (Giant Impact Hypothesis). Student 2 argues the Moon was a separately formed body captured by Earth's gravity. The Moon's oxygen isotope ratios are nearly identical to Earth's. This evidence:

Accepted Answer

Supports Student 1, since a collision would mix Earth's material into the Moon

Answer

Identical oxygen isotope ratios suggest the Moon formed from the same material as Earth — consistent with the Giant Impact Hypothesis (Student 1). Captured foreign bodies typically have distinct isotope signatures.

Question 4

Researcher A claims a new insecticide is safe for bees because lab tests showed no bee mortality at recommended concentrations. Researcher B claims the insecticide is dangerous because field studies showed 40% colony collapse. Which methodological factor best explains the difference?

Accepted Answer

Lab conditions cannot replicate complex field exposures — bees in the field encounter sublethal doses through food, water, and multiple routes simultaneously

Answer

Lab tests isolate a single variable; field exposures are complex and cumulative. Sublethal but repeated exposures through pollen, water, and combined stressors can cause colony collapse even when single doses appear safe.

Question 5

Geologist 1 argues that the Grand Canyon was carved gradually over millions of years by the Colorado River. Geologist 2 argues it was carved rapidly by catastrophic flooding from a glacial lake overflow. Which finding would most support Geologist 1?

Accepted Answer

Sediment layers within the canyon showing consistent, gradual deposition rates over millions of years

Answer

Consistent gradual deposition over millions of years directly supports slow carving (Geologist 1). Giant ripple marks, lake bed sediments, and recent dating would support catastrophic flooding (Geologist 2).

ACT Practice Test

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Free ACT Science: Conflicting Viewpoints Questions and Answers 2