A black market is:

a)Something that happens when producers sell goods for a greater price than the government mandated price ceiling.

b)A characteristic of a surplus or excess supply condition.

c)Legal but frowned upon by economists who feel it violates consumer sovereignty.

d)None of the above.

The marginal rate of substitution:

a)Is constant at all points on the budget line.

b)Increases in absolute value as one moves southeast along an indifference curve.

c)Decreases in absolute value as one moves southeast along an indifference curve.

d)May increase or decrease in absolute value as one moves southeast along an indifference curve, depending upon whether the substitution or income effect is dominant.