Take this Exam: GED and HiSET science — evidence and conclusions | Zestly

Question 1

A study shows that students who use tablets for homework score higher on tests. The researchers conclude that tablets improve learning. What is a potential flaw in this conclusion?

Accepted Answer

Students who have tablets might also have more resources for tutoring.

Answer

The study did not use enough students.

Answer

The test scores were not high enough to be significant.

Answer

Tablets are too expensive for most schools.

Question 2

A scientist tests if a new soil additive increases crop yield. She finds that the plants with the additive grew 5% taller. However, the study did not measure the weight of the fruit. Does this result answer the question of whether the additive increases yield?

Accepted Answer

No, because height is not the same as the amount of fruit produced.

Answer

Yes, because height is directly related to yield.

Answer

Yes, because any growth indicates a successful yield.

Answer

No, because the study should have lasted for a full year.

Question 3

A study of 1,000 people finds that those who exercise daily report feeling happier. What does increasing the sample size to 1,000 accomplish?

Accepted Answer

It reduces the influence of individual outliers.

Answer

It proves that exercise causes happiness.

Answer

It eliminates the need for a control group.

Answer

It ensures that everyone in the study exercises the same amount.

Question 4

A company claims their new engine is 20% more fuel-efficient. A test shows the engine uses less fuel at 40 mph, but uses more fuel at 70 mph. Does the data support the claim?

Answer

Yes, because it is more efficient at 40 mph.

Answer

No, because the efficiency is not consistent across all speeds.

Answer

Yes, because the average efficiency is higher.

Answer

No, because the test was only performed at two speeds.

Question 5

In a trial with two hundred office workers, a vitamin supplement reduced reported fatigue compared with a group that received none. What would be the most useful next experiment?

Answer

Give the supplement to the same two hundred workers again, which would confirm the result beyond doubt.

Answer

Test whether the supplement changes the color of the workers' eyes.

Answer

Test whether workers who take the supplement also type faster.

Answer

Give it to a different group, such as people doing heavy physical work, to find out whether the effect holds outside the first group.

Question 6

A study concludes that a new diet plan causes weight loss because participants lost an average of 5 pounds. The study did not track how much exercise the participants did. Why is the conclusion potentially invalid?

Answer

The weight loss could be attributed to increased exercise rather than the diet.

Answer

The study should have lasted longer than one month.

Answer

Five pounds is not a significant amount of weight to lose.

Answer

The study did not include a survey about the participants' favorite foods.