1.A large flea market is held at the local fairgrounds on the first Saturday of each month.The rates at which people enter and leave the fairgrounds are recorded for a 3-hour period beginning when the market is open to the public.The rate at which people arrive is modeled by the function A(t)=42 sin(0.03t-0.7)+7. The function L(t)=42 sin(0.34t-1.52)+42models the rate at which people leave the fairgrounds.BothA(t)and L(t)are measured in people per minute andtis measured for0 < t < 180minutes.When the count begins att=0, there are already 1572 people in the flea market area of the fairgrounds.

Answer all parts in complete sentences including units.

a)How many additional people arrive for the flea market during the 3-hour period after it opens to the public?

b)Write an expression forp(t), the total number of people at the flea market at time.

c)Find the value of p'(75)andexplain its meaning.