Urgently need help!!! I will mark the best answer as Brainliest!

Answer:
the answer is 20 years
Step-by-step explanation:
i used a website
i=p times r times t
P is the principal amount, $500.00.
r is the interest rate, 2.5% per year, or in decimal form, 2.5/100=0.025.
t is the time involved, 20....year(s) time periods.
So, t is 20....year time periods.
To find the simple interest, we multiply 500 × 0.025 × 20 to get that:
The interest is: $250.00