Marie has a small publishing company that produces textbooks. She has fixed costs of $1800/month and hires workers (assume the only thing necessary to produce more books is to hire more labor) for $2000/month. The table shows Marie's monthly production function. With as much precision as possible, calculate the following;

a. Total Cost of production when four workers are employed.

b. The output level that produces the lowest average total cost

c. The price that Marie must charge in order to break even on the production of 130 textbooks.