1) The free fall motion of the grapefruit is an uniformly accelerated motion, with constant acceleration equal to

, therefore the distance covered by the grapefruit in a time t is equal to

Substituting

, we get how far the grapefruit dropped:

2) The speed at time t in an uniformly accelerated motion of free fall is given by

where

is the initial speed, that in this case was zero. Therefore, using t=0.89 s we can find the speed just before the grapefruit hits the ground:
