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2. The following formula can be used to find the number of years t required to multiply an investment m times when r is the per annum interest rate compounded n times a year. In(m) n In(1 + *) (a) (10 Points) How long will it take to triple the value of a savings account that compounds monthly at the rate of 4%? m = triple the value (3) r = rate of 4.1 n = compounded monthly t = In (3 ) 12 In ( 1 + : 24) ~ 127.5 years (b) (15 points) All the banks in the area have savings accounts that compound semi-annually. Suppose that you want to double your initial investment in 10 years. What should be the interest rate of your savings account be in order to attain this