An automobile engine has a maximum power output of \(70 \mathrm{hp}\), which occurs at an engine speed of \(2200 \mathrm{rpm}\). A \(10 \%\) power loss occurs through the transmission and differential. The rear wheels have a radius of \(15.0 \mathrm{in}\). and the automobile is to have a maximum speed of \(75 \mathrm{mph}\) along a level road. At this speed, the power absorbed by the tires because of their continuous deformation is \(27 \mathrm{hp}\). Find the maximum permissible drag coefficient for the automobile at this speed. The car's frontal area is \(24.0 \mathrm{ft}^{2}\).