Question

Ice is forming on a pond at a rate given by
inches per hour, dy/dt=square root of t/2

where y is the thickness of the ice in inches at time t measured in hours since the ice started forming.



(a) Estimate the thickness of the ice after 15 hours.

Enter an answer to two decimal places.

B) At what rate is the thickness of the ice increasing after 15 hours?

I figured out how to do part B but I am stuck on A! please help!