Answer: He has earned $200 interest and the balance of his account is $1,200.
Step-by-step explanation:
Given: Principal : P = $1,000
Simple interest rate : r = 5% = 0.05
Time: t = 4 years
Simple interest =
i.e. Simple interest = $200
Balance of account = Principal + Simple interest
= $1,000 + $200
= $1,200
Hence, he has earned $200 interest and the balance of his account is $1,200.