Solve the Problem $f ( x ) = \frac { 2.8 x } { 100 - x }$

Multiple Choice

Solve the problem.
-Suppose a cost-benefit model is given by $f ( x ) = \frac { 2.8 x } { 100 - x }$ , where $y$ is the cost in thousands of dollars for removing x percent of a given pollutant. Find the cost of removing $80 \%$ to the nearest dollar.

A) $\$ 2240$
B) $\$ 11,200$
C) $\$ 4000$
D) $\$ 2800$