Very confused on this question, please help!

P6-13 Calculating APR (LO4] Find the APR, or stated annual rate, in each of the following cases. Required: (a) An effective annual interest of 10% (the APR is compounded semiannually) (Click to select) (b) An effective annual interest of 8% (the APR is compounded monthly) (Click to select)) (c) An effective annual interest of 19% (the APR is compounded weekly) (Click to select) (d) An effective annual interest of 18% with infinite (or continuous) compounding (Click to select)