Solve the Problem $y = \frac { 3.6 x } { 100 - x }$

Multiple Choice

Solve the problem.
-Suppose a cost-benefit model is given by $y = \frac { 3.6 x } { 100 - x }$ , where $y$ is the cost in thousands of dollars for removing $x$ percent of a given pollutant. Find the cost of removing $90 \%$ to the nearest dollar.

A) $\$ 3600$
B) $\$ 32,400$
C) $\$ 3240$
D) $\$ 9000$