The Revenue R (In Dollars) Generated by the Sale of X

Multiple Choice

The revenue R (in dollars) generated by the sale of x units of a digital camera is given by $( x - 145 ) ^ { 2 } = - \frac { 5 } { 7 } ( R - 29,435 )$ .Approximate the number of sales that will maximize revenue.

A) Maximum revenue occurs at $x = 4,205$ units.
B) Maximum revenue occurs at $x = 406$ units.
C) Maximum revenue occurs at $x = 145$ units.
D) Maximum revenue occurs at $x = 29,435$ units.
E) Maximum revenue occurs at $x = 21,025$ units.