Consider the following economic events. a. Political turmoil in the Middle East causes oil prices to skyrocket, acting as a negative supply shock on the US economy. This negative supply shock makes private investment less productive, decreasing the expected future MPK at each level of capital stock. Show how this change affects the desired level of capital and investment. Explain and show graphically (hand-drawn). b. Now, assume that there’s a significant improvement in the technology underlying electric vehicles, to such a degree that the price of electric cars is cut by more than half (you can get a Tesla for less than $20,000!). Use the saving-investment diagram to analyze the effects of this technological advancement on national saving, investment, and the real interest rate. Explain and show graphically (hand-drawn).