If real salaries decrease but nominal salaries do not, this means that

The owner of a produce store found that when the price of a head of lettuce was raised from 50 cents to $1, the quantity sold per hour fell from 18 to 8. The arc elasticity of demand for lettuce is

A) -0.56. B) -1.15. C) -0.8. D) -1.57.

In panel data, the regression error

A) is likely to be correlated over time within an entity B) should be calculated taking into account heteroskedasticity but not autocorrelation C) only exists for the case of T > 2 D) fits all of the three descriptions above