A gas tank on a dock has a small puncture and is leaking gas at the rate of

1cm^3/min into a lake. It forms a circular slick that is 1mm thick on the surface of the water.

a) Find the amount of gas leaked as a function of time.

b) State the radius of the slick as a function of its volume

c) State the radius of the slick as a function of time.

d) What is the radius of the slick after 40 minutes?