Please explain:

*Why the correct answer is correct,

*Why the other ones are incorrect or not the best answer.

1) As interest is recorded on an interest-bearing note, the Interest Expense account is ______.

a) decreased; the Interest Payable account is increased.

*b) increased; the Interest Payable account is increased. (correct answer)

c) increased; the Notes Payable account is decreased.

d) increased; the Notes Payable account is increased.

2) Which of the following is true of a variable cost?

a) Total variable cost remains constant with changes in the number of goods sold.

b) Unit variable cost decreases with an increase in production.

*c) Unit variable cost remains constant with changes in production. (correct answer)

d) Total variable cost decreases with an increase in the number of goods sold.