11. Which of the following statements is false?

a. MC is given by the slope of TC or the slope of TVC.

b. An isoquant curve identifies the different combinations of inputs that can be used to produce a fixed

rate of output.

c. The law of diminishing returns to labor input in the short run is due to the fact that capital input is fixed.

d. Average fixed cost is fixed regardless of the quantity of output to produce.

e. In the long run all production inputs are variable.

f. Demand curve facing a price-taking firm is horizontal at the market price.