math help with rates in calculus

Question

At a processing plant, over the course of an 8-hour day, workers move material into a pile, which is removed at a constant rate by a conveyor belt. The workers move material into the pile at rate 200e^−0.5t

units/hr while the conveyor belt removes the material at 50 units/hr.

(a) Find the net change in the size of the pile over the first 2 hours, and over the first 8 hours. Round your answers to the nearest hundredth.

2 hours    = units

8 hours    = units

(b) At what time is the amount of material in the pile the largest and the smallest?

largest	t =
smallest	t =

Answer 1

8hrs

worker rate=200e^(-.5t)uph

conveyer=50uph

p=2.71828182...

200*2.72^(-.5*2)=

2 hrs=200*.3678=73.576

8hrs=200*2.72^(-.5*8)=

200*.018=3.66