"Constant velocity" is practically a definition for zero acceleration.
When the object is big enough to contract itself into a ball.
The time must be measured with respect to gravity. As it falls, it has free fall that is the force acting on it will be the gravity.With the distance in account, d = 1/2 gt²
t = √(2d/g)
He answer is A. <span>encourage agricultural usage in the watershed
if you want to read it for yourself go to
www.nature.org/ourinitiatives/regions/northamerica/unitedstates/indiana/journeywithnature/watersheds...
hope this helps you!!</span>