Bernie's Bagels can function with three different oven capacities. For any given amount of labour, a larger output can be produced with a larger-capacity oven. The cost of a small oven is $100; the cost of a medium-sized oven is $140; and the cost of a large oven is $180. Each worker is paid $60 per shift. The production levels for each plant size are given in the table below.
(a) Compute and graph AP and MP curves for each size of operation.
(b) Verify that the relationship between the AP and MP curves is as it should be.