If the Total Cost Function for a Product Is $C ( x ) = 200 + 4 x + 0.09 x ^ { 2 }$

Multiple Choice

If the total cost function for a product is $C ( x ) = 200 + 4 x + 0.09 x ^ { 2 }$ dollars. Find the minimum average cost.

A) $\$ 15.00$
B) $\$ 23.00$
C) $\$ 13.03$
D) $\$ 12.49$
E) $\$ 11.00$