Which elements are most likely to donate one electron?

Acar drives toward the right over the top of a hill, as shown below. which arrow represents the centripetal acceleration? w x y z

You throw a small rock straight up from the edge of a highway bridge that crosses a river. the rock passes you on its way down, 7.00 s after it was thrown. what is the speed of the rock just before it reaches the water 28.0 m below the point where the rock left your hand? ignore air resistance.

Avehicle accelerates from 0 to 30 m/s in 10 seconds on a straight road