Hello I have an economics math equation and have provided the question via image. I need help with

Under a progressive tax system: Q a. the average tax rate falls with increases in real GDP. 0 b. the average tax rate increases with increases in real GDP. 0 c. the average tax rate remains constant With changes in real GDP. 0 cl. government tax receipts decrease When the economy is expanding. 0 e. government tax receipts increase when the economy is in a recession