A firm's marginal product curve slopes downward throughout its length

Suppose that a monopolistically competitive firm is in long-run equilibrium. The firm's demand curve is tangent to its average cost curve at Q = 25 . Average cost is minimized at Q = 35, where average cost is $50 . Which of the following is true?

a. This firm maximizes profit at an output level of 25 units. b. This firm maximizes profit at an output level of 35 units. c. This firm maximizes profit at an output level less than 25 units. d. This firm maximizes profit at an output level greater than 35 units. e. There is not enough information to find the firm's profit-maximizing level of output.

Wanda owns a lemonade stand. She produces lemonade using five inputs: water, sugar, lemons, paper cups, and labor. Her costs per glass are as follows: $0.01 for water, $0.02 for sugar, $0.03 for lemons, $0.02 for cups, and $0.10 for the opportunity cost of her labor. She can sell 300 glasses for $0.50 each. What are Wanda's implicit costs per glass?

a. $0.18 b. $0.10 c. $0.08 d. $0.02