Which of the following best describes why the predicted incremental earnings arising from a given decisionnare not sufficient in and of themselves to determine whether that decision is worthwhile? a) they do not show how the firm's earnings are expected to change as the result of a particular decision. b) they are not easily predicted from historical financial statements of a firm and its competitors. c) these earnings are not actual cash flows. d) they do not tell how the decision affects the firm's reported profits from an accounting perspective.

David consumes two things: gasoline (g) and bread (b). david's utility function is u(g, b) = 10g^0.25 b^0.75. use the lagrange technique to solve for david's optimal choices of gasoline and bread as a function of the price of gasoline, p_g, the price of bread, p_b, and his income m. with recent decrease in the price of gasoline (maybe due to external shock such as shale gas production) does david increase his consumption of gasoline? for david, how does partial differential g/partial differential p_g depend on his income m? that is, how does david's change in gasoline consumption due to an increase in the price of gasoline depend on his income level? to answer these questions, find the cross-partial derivative, |partial differential^2 g/partial differential m partial differential p_g.