What is the total american opportunity & lifetime tax credit the jones family can take, given the following information? 1) sally is a sophomore and incurs $5,000 in education expenses. 2) tommy is in grad school and incurs $7,000 in education expenses. 3) mom, who has a 4 year degree, goes back to school and incurs $4,000 in education expenses.

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.