Macroeconomics equations, economics homework help

Answer the following questions about marginal propensity to
consume and the multiplier. First provide the correct equation and
then show your work to arrive at the answer:

1. What is the marginal propensity to
   consume when consumption changes from 7 to 6 and disposable income
   changes from 5 to 3?

2. If disposable personal income is
   10 and consumption is 12, what is personal savings? What
   does this mean?

3. What is the multiplier when the
   change in equilibrium level of real GDP in the aggregate
   expenditures model is 9, and change in autonomous aggregate
   expenditures is 3?

4. What is the multiplier when the
   marginal propensity to save is 1/3?

5. What would happen to the marginal propensity to save when a
   tax cut was enacted causing the multiplier to change to 5?

The following criteria will be used to grade the papers:

• Correct equations are used and
  shown

• Explanations are correct

• Calculations are correct. 

• Answers are correct