a. The interest for the first payment is $40.
b. The interest for the seventh payment is $29.27.
In financial accounting and management, interest refers to the finance charge for obtaining or giving a loan or credit.
The interest payment or revenue is based on the interest rate applied to the principal or loan balance.
Loan = $3,200
Monthly payment = $199.68
Interest rate = 15%
Loan balance after 6 payments = $2,341.45
Interest for the first payment = $40 ($3,200 x 15% x 1/12)
Interest for the seventh payment = $29.27 ($2,341.45 x 15% x 1/12)
Thus, while the interest for the first payment is $40, the interest for the seventh payment is $29.27.
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