Social security tax that is 6.2% of her gross pay medicare tax that is 1.45% of her gross pay state tax that is 21% of her federal tax determine how marilyn’s net pay will be affected if she increases her federal withholding allowances from 3 to 4. a. her net pay will increase by $15.00. b. her net pay will decrease by $15.00. c. her net pay will increase by $18.15. d. her net pay will decrease by $18.15.