Solve the Problem $$p = - \frac { 1 } { 5 } x + 500 , \{ x \mid 0 \leq x \leq 500 \}$$

Multiple Choice

Solve the problem.
-The price p and the quantity x sold of a certain product obey the demand equation: $$p = - \frac { 1 } { 5 } x + 500 , \{ x \mid 0 \leq x \leq 500 \}$$ What is the revenue to the nearest dollar when 400 units are sold?

A) $10,000
B) $250,000
C) $232,000
D) $168,000