When katie was born her mother invested $5000 in an account for her college savings. the interest rate is 3.5% compounded annually. to represent this, we can use the formula v = 5000(1 + r)t where r represents the interest rate and t represents the time in years. how much will katie have in her account when she turns 18? a) $5,175 b) $7,127 c) $9,287 d) $12,472