If the Demand Function for a Certain Commodity Is $p ( x ) = 4 - \frac { x } { 30 }$

Multiple Choice

If the demand function for a certain commodity is $p ( x ) = 4 - \frac { x } { 30 }$ and the consumer surplus is 15, what should be the production level?

A) 90
B) 45
C) 15
D) 70
E) 30
F) 60
G) 20
H) 80