4. [10 points) At a COVID-19 testing center, 300 tests are conducted in each day. The facility employs 4 employees working in 7.5-hour shifts per day. a. What is the productivity per labor-hour? Answer should include units and should be expressed in a sentence. Show all calculations. b. In the testing center, the fixed costs per day is $1,000. Daily cost for wages is $1,500. Supplies and utilities cost $2,500 per day. What is the productivity per dollar of input? Answer should include units and should be expressed in a sentence. Show all calculations