Calculate the interest due on the following credit card balances:

A) An unpaid balance of $1629.53 at a rate of 19.50% for 21 days
B) An unpaid balance of $2639.99 at a rate of 22.95% for 30 days.

A. I = Po^r*t = 1629.53*(0.1950/365)*21 = $18.28

B. Same procedure as A.

To calculate the interest due on the credit card balances, you need to use the formula:

Interest = (Balance * Rate * Time) / 365

where:
- Balance is the unpaid balance on the credit card
- Rate is the annual interest rate as a decimal
- Time is the number of days

Let's calculate the interest due for each case:

A) An unpaid balance of $1629.53 at a rate of 19.50% for 21 days:
Interest = (1629.53 * 0.195 * 21) / 365
Interest = $14.97

Therefore, the interest due for Case A is $14.97.

B) An unpaid balance of $2639.99 at a rate of 22.95% for 30 days:
Interest = (2639.99 * 0.2295 * 30) / 365
Interest = $59.20

Therefore, the interest due for Case B is $59.20.

To calculate the interest due on credit card balances, we need to use the formula:

Interest = (Principal balance) x (Annual interest rate) x (Number of days) / (Number of days in a year)

Let's calculate the interest due on each credit card balance:

A) Unpaid balance of $1629.53 at a rate of 19.50% for 21 days:

Interest = $1629.53 x 0.1950 x (21 / 365)
≈ $15.12

Therefore, the interest due on this balance is approximately $15.12.

B) Unpaid balance of $2639.99 at a rate of 22.95% for 30 days:

Interest = $2639.99 x 0.2295 x (30 / 365)
≈ $53.49

Therefore, the interest due on this balance is approximately $53.49.