A US Company and a Japanese Company Sells an Identical Product

A U.S. company and a Japanese company sells an identical product in the Japanese market. The inverse demand equation for this product is P_J = 10 !0.5(Q_JUS + Q_{J J}) . Suppose that the best-response functions of the U.S. and Japanese companies are Q_JUS = 6 !0.5Q_{J J} and Q_{J J} = 9 !0.5Q_JUS, respectively. Consumer surplus in the Japanese market is:

A) $25 million.
B) $30 million.
C) $42.5 million.
D) $45 million.
E) $60 million.