1. Let c be consumption. Under what conditions on the parameters 0 and 1 could the following...

1. Let c be consumption. Under what conditions on the parameters λ0 and λ1 could the following functions serve as utility functions for a risk-averse investor? (Remember that marginal utility must be positive and the function must be concave.)

a. U

(c) = λ0 exp(λ1c)

b. U

(c) = λ0cλ1

c. U

(c) = λ0c + λ1c2