You buy a motor boat worth $$13,400.$ You can pay cash, or chose one of two

payment options:

Option $1$: Pay $$10,000$ in one year and $$5000$ in two years

Option $2$: Pay $$17,400$ in $3$ years

If the interest rate on both options is $j_{12}=9\%,$ which one should you take and how

much cheaper is it compared to paying cash?