Question

A stone is dropped into a lake, causing circular waves whose radii increase at a rate of 30 cm/sec.
a. At what rate is the area enclosed by a circular wave increasing when the radius is 50 cm.
b. At what rate is the circumference of a circular wave increasing when the radius is 50 cm?

Answer 1

is this a calculus class?

Answer 2

B

Answer 3

You will need to define that formulas for area and circumference, and take derivatives

Answer 4

Yes this is a calculus class

Answer 5

Find a formula that relates the area of a circle to its radius.