Use the annual compound interest formula to find the amount in the savings account at the end of the time period and then find the total interest earned.
$8,000 at 5% for 3 years.
It is one of these answers if it helps...
$12,700 in account $4,700 interest
$10,520 in account $2,520 interest
$8,315 in account $315 interest
$9,216 in account $1,261 interest