Which of the following statements are true?

a) If at the current price, demand is inelastic, raising the price will increase the monopolist's revenue.

b) Between two gambles, a risk averter will always choose the one with a smaller variance.

c) A rational person will not save money if the interest rate is less than the inflation rate.

d) A monopolist with positive marginal cost who charges a uniform price always prices on the inelastic portion of the demand curve.