Uhm.. yeah

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length