A Firm's Average Cost Function Takes the Form $$A C = 4 Q + a + \frac { 6 } { Q }$$

A firm's average cost function takes the form $$A C = 4 Q + a + \frac { 6 } { Q }$$ and it is known that MC = 35 when Q = 3. Find the value of AC when Q = 6.

A) 11
B) 25
C) 59
D) 36
E) 216