mr walsh forgot a savings account that he opened with $3000 that earned interest rate of 2% per year. when he checked his account balance is $3,330 how long did he leave the account for

The pyraminx is a rubik's cube-type toy in the shape of a tetrahedron. the pyraminx shown below has edges 15\,\text{cm}15cm long and vertical height h=12.2\,\text{cm}h=12.2cm. the triangle drawn with dashed lines is a right triangle. what is the distance rr? round your answer to the nearest tenth.