Solve the Problem $C ( x ) = 66 + 720 x$

Solve the problem.
-An-Mei owns a business making and selling jackets. She has a fixed cost of $720. It costs $66 to produce each jacket. The selling price is $78 per jacket. Let x represent the number of jackets produced and sold and write the cost function, C, and revenue function, R.

A) $C ( x ) = 66 + 720 x$
$\mathrm { R } ( \mathrm { x } ) = 78$
B) $C ( x ) = 66 x + 720 x$
$R ( x ) = 78 x$
C) $C ( x ) = 66 + 78 x$
$R ( x ) = 720 x$
D) $C ( x ) = 66 x + 720$
$R ( x ) = 78 x$ nd revenue function, R.