Computation of Tax Credits. During the current year, Becky has personal credits (P) as well as business credits (B) related to her sole proprietorship. Her tentative tax credits for the current year include the following: Child tax credit Disabled access credit Child and dependent care credit1,200 P Business energy credit S 2,000 P $ 900 B 600 B Becky's regular tax liability before credits is $4,000. Her tentative alternative minimum tax is $O a. What is the amount of allowable personal tax credits? b. What is the amount of allowable business tax credits? c. What treatment is accorded to the unused tax credits for the current year