One Building Has Parallel Elevator Shafts for a Passenger Elevator

Essay

One building has parallel elevator shafts for a passenger elevator P and a freight elevator F. Assume that each elevator moves at (its) steady speed and can start and stop instantly. One time during a particular day, P and F start trips at the same time. After 2 minutes, P was 400 feet from the bottom of the shafts, heading down, and F was 120 feet from the bottom, heading up at a speed of 20 feet/minute. Four minutes after the start of the trip, P was 280 feet from the bottom of the shafts.
A) Write an equation describing the height h of elevator P (in feet) above the bottom of the shafts, t minute(s) after the start of the trip.
B) At what height did elevator P start the trip, and what was its speed?
C) Write an equation describing the height h of elevator F (in feet) above the bottom of the shafts, t minute(s) after the start of the trip.
D) When the trips started, where was elevator F?
E) When, if ever, were the two elevators at the same height above the bottom of the shafts? If they were at the same height, what was that height?