Refer to the diagram. Which tax system has the most built-in stability?

The unemployment rate is calculated by dividing the number of unemployed and looking for work by the sum of the number employed and the number unemployed and looking for work

Indicate whether the statement is true or false

The fictional country of Alpetra increases the income tax rate so that tax revenues increase by $70 million. Government spending also increases by $70 million and consumption falls by $10 million. If GDP remains the same and Alpetra is a closed economy, then investment

a. increases by $140 million. b. increases by $70 million. c. decreases by $60 million. d. decreases by $80 million.