Robert Z. answered 08/17/20
3965+ hours (& counting!) tutoring math -- Prealgebra to Calculus 2
Option 1 will add 6% of $2500 at the end of each year for 20 years. That adds 20($150), or $3000, for a total of $5500.
Option 2 uses the compounding formula P = P0(1 + r/n)nt, where P is the final amount, P0 is the initial amount, r is the annual interest rate, n is the number of compounding periods per year, and t is the number of years.
Applying that, we have P = $2500(1 + .04/12)240 = $5556.46
Option 3 uses the continuously compounding formula P = P0(1+ert) = $2500·(1+e.035·20) = $7534.38