Please show the explanation if you can.

Roberto's salary is $138,700 in 2020. Roberto is paid on a semimonthly basis, is single, and claims one dependent. Assume that his employer uses the percentage method table. Use percentage method tables for a manual payroll systems. Required: a. What is Roberto's federal tax withholding per pay period? b. What is Roberto's FICA withholding per pay period before he reaches the social security limit? c. For the last pay period in 2020, what is Roberto's FICA withholding? (For all requirements, round your intermediate computations and final answers to 2 decimal places.) Amount a Federal tax withholdings b. FICA withholdings C FICA withholdings