Question

jump from a plane 13000 feet above sea level landing in a valley at 120 feet below sea level. open shoot after falling 10500 feet from the plane. How much farther will she fall in feet to reach the valley floor

Answer 1

The total distance between the valley and plane is equal to:
13000-(-120)
13000+120
=14200

To find out how much further to fall subtract the height at which the parachute was opened from the total height...
14200-10500
=3700 feet

She will need to fall another 3700 feet to reach the valley floor.

Hope this helps!
-Benjamin