You are in desperate need of cash and turn to your uncle, who has offered to lend you some money. You decide to borrow $1,320 and agree to pay back $1,520 in two years. (a 1) What annual interest rate is your uncle charging you? (If you solve this problem with algebra round intermediate calculations to 4 decimal places, in all cases round your final answer to two decimal places, e.g. 8.72%.) Rate of interest charged by uncle %