Tunica sells widgets in a perfectly competitive market. Below are its short-run total variable costs at different output levels. The firm's fixed cost is $12. The market price for one widget is $14.

Units Total Variable Cost

0 $0

1 $12

2 $25

3 $60

4 $120

5 $200

6 $300

1. What is the average total cost of the 6th unit?
2. What is the first unit of output where diminishing marginal returns have begun?
3. What profit or loss would Tunica earn at its profit maximum? Show your work.
4. Would Tunica operate in the short run? Explain.
5. Would Tunica stay in the market in the long run? Explain.