a. If the opportunity cost of capital is 11%, which project(s) have a positive NPV? b. Calculate the payback period for each project. c. Which project(s) would a firm using the payback rule accept if the cutoff period is three years? Complete this question by entering your answers in the tabs below. If the opportunity cost of capital is 11%, which project(s) have a positive NPV? Note: Do not round intermediate calculations