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An oil well off the Gulf Coast is leaking, with the leak spreading oil over the

ID: 2911524 • Letter: A

Question

An oil well off the Gulf Coast is leaking, with the leak spreading oil over the water's surface as a circle. At any time t, in minutes, after the beginning of the leak, the radius of the circular oil slick on the surface is r(t) equals = 3t feet. Let A(r) equals = (pi r squared) r^2 represent the area of a circle of radius r.

(a) Find (A r)(t).

(b) Interpret (A r)(t).

(c) What is the area of the oil slick after 3 min?

(a) (A circle r)(t) = (Simplify your answer. Type an exact answer, using pi as needed.)

(b) It defines _____ in terms of ____ .

(c) The area of the oil slick after 3 min is _____ ft^2. (Simplify your answer. Type an exact answer, using pi as needed.)

Explanation / Answer

r(t) = 3t

A(r) = pir^2

a) (Aor)(t) = pi ( 3t)^2

= 9pit^2

b) it defines area in terms of time

c) area of the slick after 3 min

area = 9pi(3)^2

= 81pi