A ______ is a private good.

For a monopolist with a downward-sloping demand curve,

a. the coefficient of price elasticity of demand is infinite. b. the coefficient of price elasticity of demand is zero. c. as price increases, marginal revenue decreases. d. as price decreases, marginal revenue decreases. e. when the price is equal to zero, marginal revenue is equal to zero.

A rightward shift of the investment demand curve will:

A.  Shift the investment schedule downward B.  Shift the investment schedule upward C.  Decrease the quantity of investment D.  Decrease the real rate of interest