Refer to the Following

Multiple Choice

Refer to the following:

A firm produces 4,000 units of output using 500 workers. Marginal cost is $10, the wage rate is $160, and total fixed cost is $100,000.

-What output is 4,000 units,

A) average variable cost is decreasing.
B) average variable cost is increasing.
C) average total cost is decreasing.
D) average total cost is increasing.
E) both a and c