Here is the problem:

"A spherical container with a radius of 15cm is being filled at a constant rate of 250╥ ml/sec. What is the height of the liquid from the bottom of the container after 4.5 seconds?"

I think you need to use disk integration to solve this one, but I am not sure. I could be over thinking this one.

Also, is it possible to derive an equation representing the height of the liquid as it is being filled vs time?