Determine the maximum contribution that can be made to a Keogh plan in each of the following cases. In all instances, the individual is self-employed, and the self-employment tax reduction has already been taken. a. Self-employment income of $61,000. b. Self-employment income of $61,000 and wage income of $35,000. c. Self-employment income of $155,000. d. Self-employment income of $300,000. a. Maximum Keogh plan contribution $ 12,200 b. Maximum Keogh plan contribution c. Maximum Keogh plan contribution $ 12,200 $ 31,000 d. Maximum Keogh plan contribution $ 56,000