Suppose that disposable income, consumption, and saving in some country are $200 billion, $150 billion, and $50 billion, respectively. Next, assume that disposable income increases by $20 billion, consumption rises by $18 billion and saving goes up by $2 billion.

1.What is the economy's MPC?

2.What is its MPS?

3.What was the APC before and after the increase in disposable income?