Exhibit 9.4 -Refer to Exhibit 9.4,which Shows the Total Cost and Total

Exhibit 9.4
-Refer to Exhibit 9.4,which shows the total cost and total revenue curves for a monopolist.The total profit earned by the monopolist at the profit-maximizing output is _____

A) $20.
B) $30.
C) $0.
D) $70.
E) $40.