A Firm Is Producing Two Goods (X and Y)that Are $$Q _ { d } = 120 - 4 P _ { x } - 10 P _ { y }$$

Multiple Choice

A firm is producing two goods (X and Y) that are related in consumption.The demand function for X is: $$Q _ { d } = 120 - 4 P _ { x } - 10 P _ { y }$$ In order to maximize profit,the firm

A) should determine jointly the levels of output for the two goods.
B) should treat the price of Y as given when determining the optimal production of good X.
C) should choose the levels of output for goods X and Y at which total marginal revenue equals total marginal cost.
D) both a and b
E) both a and c