4m - 4 = 4m

Help please

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)

What three-dimensional solid have 6 rectangular faces, 2 equal bases that are not rectangles and 18 edges

What is the sum of the first 8 terms of the geometric series