Pre-Calc Help!

Question

The spreag from of oil leaking from a tanker is in the shape of a circle. If the radius r (in feet) of the spread after t hours is r(t) = 200sqt(t), find the area A of the oil slick as a function of t.

Answer 1

Area = pi * radius^2

 

        = pi * [200*Sqrt(t)]^2

 

        = pi * 40000 * t

 

CHECK:

 

  After 100 seconds, the radius is  200*sqrt(100)  = 200 * 10 = 2000 feet.

 

  The area of the circle with radius 2000 is   pi * 4000000 = A(100)    <--- 4 zeros + 2 zeros = 6 zeros