Marcus wants to test the effect of gravity on objects with different
masses. He drops two footballs from a first-floor window, a second�floor window, and a third-floor window. In each case, he times how
long it takes the footballs to reach the ground. What is wrong with his
experimental design? (1 point)
The windows are not high enough to show significant differences in
the drop times.
It does not include objects with different shapes.
It does not include objects with different masses.
The drops are not repeated.