A student designs a gravity experiment. She will time how long it takes different objects to fall from her school's roof to the ground. She will use three objects: a 2-foot-long board, a toy car, and a paper bag. What is wrong with her experiment's design? (1 point) The school roof is not tall enough to test the effect of gravity on different objects. Gravity will not affect how long it takes for the objects to fall to the ground. The experiment does not test enough objects. The objects do not have the same size, shape, or mass, so any differences in drop times cannot be attributed to one variable.

The main issue with the student's experiment design is related to the **control of variables**. For a fair test, all variables except the one being tested (in this case, the effect of gravity) should be kept constant. However, the objects chosen—a 2-foot-long board, a toy car, and a paper bag—differ significantly in size, shape, and mass. These differences can influence the fall times due to factors like air resistance and inertia, making it difficult to isolate gravity as the sole variable affecting the results. **Correct Answer:** *The objects do not have the same size, shape, or mass, so any differences in drop times cannot be attributed to one variable.* **Answer:** The objects do not have the same size, shape, or mass, so any differences in drop times cannot be attributed to one variable.