Chapter 4.1, Problem 42E

Ecology The cost $C$ (in millions of dollars) of removing $p\%$ of the industrial and municipal pollutants discharged into a river is given by

$C=\frac{225p}{100-p},0\le p<100.$

(a) Use a graphing utility to graph the cost function.

(b) Find the costs of removing $10\%,40\%,\text{ and }75\%$ of the pollutants.

(c) According to the model, is it possible to remove $100\%$ of the pollutants? Explain.