Refer to the Following $$\begin{array} { l } Q _ { d } = 120 - 10 P \\M C _ { A } = 4 + ( 1 / 5 ) Q _ { A } \\M C _ { B } = 6 + ( 1 / 10 ) Q _ { B }\end{array}$$

Multiple Choice

Refer to the following.
A firm with two plants, A and B, has the following estimated demand and marginal cost functions:
$$\begin{array} { l } Q _ { d } = 120 - 10 P \\M C _ { A } = 4 + ( 1 / 5 ) Q _ { A } \\M C _ { B } = 6 + ( 1 / 10 ) Q _ { B }\end{array}$$
-How should the firm allocate total output between the two plants in order to maximize profit?

A) produce 5 units in plant A, 10 units in plant B
B) produce 15 units in plant A, 10 units in plant B
C) produce 20 units in plant A, 20 units in plant B
D) produce 20 units in plant A, 25 units in plant B
E) none of the above