On a certain workday, the rate, in tons per hour, at which unprocessed gravel arrives at a gravel processing plant is

modeled by G(t) = 90 + 45 cos (t), where t is

measured in hours and 0
the workday (t=0), the plant has 500 tons of unprocessed

gravel. During the hours of operations, 0
plant processes gravel at a constant rate of 100 tons per

hour.

c.) Is the unprocessed gravel at the plant increasing or

decreasing at time t=5 hours? Show the work that leads

to your answer.