Suppose the federal government had budget surpluses of $80 billion in year 1 and $120 billion in year 2 but had budget deficits of $10 billion in year 3 and $40 billion in year 4. also assume that it used its budget surpluses to pay down the public debt. at the end of these four years, the federal government's public debt would have:

The best answer for this question would be that it will be decreased by $150 billion.

Because since we are following the rules of Budget Surplus which states that the income or receipts have increased the outlays of its expenditures. It is commonly known in the term “savings” and what we refer to the financial states of the government.