economics puzzle

3. variable ____ is any production cost that changes as output changes
6. the total ____ of the firm per period
7. A firm in the short run chooses the output ____ where marginal revenue equals marginal cost.
9. As long as marginal product is ______, total product continues to increase.
11. Elasticity of supply indicates how _____ producers are to a change in price.
12. cost depends on the amount of labor employed and on the wage.
14. _____ cost is independent of the firms output
15. ____ of a supply curve is the increase or decrease in supply resulting in a change in one determinants of supply other then the price of a good.

1. variable cost varies with the amount
2. ____ run is a period during which at least one of the firms resources is fixed
4. revenue is the change in total revenue from selling another unit of the good
5. ______ is the incentive that motivates the behavior of suppliers.
8. law of ____ is the quantity of a good supplied during a given time period is usually directly related to it's price.
10. Marginal product turns ______if an eighth worker is hired
13. long run is a period in ___ resources can be varied