A tumor is a collection of cancerous cells. Suppose each cancerous cell is spherical and has a radius of 5 x 10-³ cm, and that the doubling time for a population of cancerous cells is 30 hours.

If the tumor has an initial volume of 0.3 cm³, how many cancerous cells does it contain? (For simplicity, assume that the tumor is entirely made of cells, that there is no space between them.) Round your answer up to the next whole number. ​