Broze Company makes four products in a single facility. These products have the following unit product costs:

Additional data concerning these products are listed below.

The grinding machines are potentially the constraint in the production facility. A total of 53,600 minutes are available per month on these machines.
Direct labor is a variable cost in this company.

Up to how much should the company be willing to pay for one additional minute of grinding machine time if the company has made the best use of the existing grinding machine capacity? (Round off to the nearest whole cent.)

A. $35.90

B. $0.00

C. $11.60

D. $8.58

Please show me the work and how you received the answer, Thank you very much!