For a new bottling machine it is developing. Future research and development expenses could range from $4 to $9 million, with a most likely value around $7 million. The life of the product will be anywhere from 3 to 10 years. Yearly unit sales will range from 100 to 500, with a most likely value around 300. The machines will sell for between $20,000 and $25,000 each. The production cost of the machine is expected to be

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.