A firm that has market power:

1. can charge whatever it wants for its product

2. can charge a price above marginal cost

3. has positive economic profit

4. does not lose sales when increasing price

If you are testing the null hypothesis, you are testing:

1. hypotheses that the coefficient for an explanatory variable is zero and the therefor has no impact on your results

2. the hypotheses that the coefficient for an explanatory variable is not zero and therefore has impact on your results

3. the hypotheses that the coefficient for a dependent variable is not zero and therefore has impact on your results

4. the hypotheses that setting a given price will yield no increase in profits