If the problem doesn't specify, then it's simple interest.
The formula for simple interest
P = Principal = 2000
r = interest rate =6% = 6/100 = .06
t = time (in years) = 5
I = interest earned = solution
I=P*r*t
I =2000*.06*5= $600
He will earn $600 in 5 years. He will have the original principal plus the interest after 5 years.
$2000+$600=$2600.
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