I did part a.) and got $2,400 billion. Need help with parts b-d.

Government Spending Multiplier Suppose that the marginal propensity to consume is 0.75. Assume that there are no tax and no import leakages. Government proposes a scal stimulus of $600 billion. (Show computation work to receive full credit.) a. Calculate the total change in real GDP in the economy. b. How much is the induced change in the private sector aggregate spending? c. Explain the spending multiplier process by comparing unemployment insurance benet to educational spending. which policy could achieve a faster effect, and why? d. What are some limitations of discretionary fiscal policy in (c) and the spending multiplier