If there were no air resistance, then the height (in feet) above the earth for a skydiver t seconds after jumping from an airplane at 10,000 feet would be given by h(t)=16t^22 + 10,000. (See the attached question file)
(1) h(t) = -16t^2 + 10000
h(t) = 0
-16t^2 + 10000 = 0
-16t^2 = -10000
On solving, we get t = 25 seconds
All parts of the problem solved showing all the steps.