Compute the effective annual rate of interest (a) for 6% compounded monthly; (b) at which $1100 will grow to $2000 in seven years compounded quarterly. (a) The effective rate of interest is % (Round the final answer to four decimal places as needed. Round all intermediate values to six decimal places as needed.) (b) The effective rate of interest is % (Round the final answer to four decimal places as needed. Round all intermediate values to six decimal places as needed.)