Final answer:
Sam has earned $700 in interest after 2 1/2 years.
Step-by-step explanation:
To calculate the amount of interest earned, we can use the formula:
Interest = Principal * Rate * Time
Given that the principal is $3,500 and the interest rate is 8% annually, we can calculate:
Interest = $3,500 * 0.08 * 2.5 = $700
Therefore, Sam has earned $700 in interest after 2 1/2 years.