A One Person Automobile Oil Change in Rural Mississippi Has $\$ 900.00$

A one person automobile oil change in rural Mississippi has a fixed overhead of $\$ 900.00$ per month. The variable cost per oil change $\$ 10.00$ . The charge is $\$ 30.00$ for one oil change. If the owner/worker Joe Smith performed 300 oil changes in November 2005; total sales revenue for November 2005 is

A) $\$ 9,000.00$
B) $\$ 6,000.00$
C) $\$ 3,000.00$
D) $\$ 8,100.00$
E) $\$ 5,100.00$