5. [5 marks] In economics, an index of risk aversion is defined as: I(m) = U" (m) U' (m) where m measures how much of a commodity is owned and U(m) is a utility function. Find the index of aversion, I(m), for both utility functions Ua(m) = Vm and Ub(m) = m'/8, and determine which indicates a greater aversion to risk