A single firm owns the only subway system in a large city. The firm has total costs in the short run given by: TC = 1080 + 10q where q is the number of riders per second using the subway and TC is the total cost per second in dollars. The demand for subway rides is given by: P = 40 - 0.2q, where q is the number of riders per second using the subway and P is the price charged to each consumer in dollars. To maximize profit, what price will the firm charge?
A) $0
B) $40
C) $35
D) $30
E) $15
F) $10
G) $20
H) $25
I) $28
J) $24