The sum of the marginal propensity to consume (MPC) and the marginal propensity to save (MPS) always equals:

Suppose that today, consumers expect the price of a gallon of gasoline to double in the future. Then today the gasoline

A) demand curve will shift to the right. B) demand curve will shift to the left. C) supply curve will shift to the right. D) supply curve will shift to the left.

For Brent, if the marginal utility of sleeping an extra hour, from 8 a.m. to 9 a.m., is negative: a. Brent is better off getting up at 8 a.m. or earlier

b. Brent is better off getting up at 9 a.m. c. Brent's total utility from sleeping must be negative. d. Brent's average utility from every hour he sleeps must be negative.