The maintenance department has two mechanics, each of whom will cost the company $25 per hour and would work separately. Each of them can repair four units of heavy equipment per 8-hour day. Currently, there is an average of four units of heavy equipment requiring daily repair (assuming Poisson arrival). A unit of heavy equipment not in operation costs the company $40 per hour, since the company must lease alternative equipment. The daily queuing related cost is approximately

a. 103.33

b. 506.67

c. 734.55

d. 826.67