Hello, I need help on these questions.I do not know the formula to solve these questions.

Siva, lnc., imposes a payback cutoff of three years for its international investment projects. Year Cash Flow (A) Cash Flow (B) 0 $ 50,000 $ 60,000 1 18,000 10,000 2 18,000 13,000 3 16,000 16,000 4 3,000 220,000 What is the payback period for both projects? (Round your answers to 2 decimal places, e.g., 32.16.) Payback period Project A years Project B years Which project should the company accept? A' Project A A' Project B