Answer:
a. Increase government spending and taxes by $100 billion
Explanation:
Based on the information given it must Increase the government spending and taxes by $100 billion ($600 billion-$500 billion)which is the amount of $600 billion which represent the amount the goverment have in case they wants to move the economy to full-employment less the economy equilibrium at $500 billion which means it have to Increase the government spending and taxes by $100 billion which is the difference between $600 billion and $500 billion.