Ricardo and Bart open savings accounts that both pay the same annually compounded rate of interest i. Ricardo deposits $600 initially and Bart deposits $1200. The amount of interest Bart earns in year 6 is X, the same amount that Ricardo earns in year 14.

a) Write down an equation for A(t), the accumulation amount for each of their accounts.

b) Solve for i.

c) Solve for X.