Wayne wants to become a lifeguard. For part of the lifeguard test, he has to float in the pool for five minutes. Why does Wayne float instead of sinking to the bottom of the pool?
A. Wayne weighs too much.
Exhibits
B. Wayne does not weigh very much.
C. Gravity pushes Wayne up against the water.
D. The water pushes Wayne up against gravity.

Which one of the following research methods can show cause and effect

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e

Consider two less-than-desirable options. in the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. in the second option you are driving 30 mph and crash head-on into a stationary brick wall. in neither case does your car bounce off the thing it hits, and the collision time is the same in both cases. which of these two situations would result in the greatest impact force?