In which of the following situations would the amounts of expense and expenditure for the period differ?

a. An aa uses and is billed for utilities but has paid only half of the amount billed at year end.

b. An entity purchases equipment for cash. The purchase occurred on the last day of the fiscal year.

c. Salaries and wages incurred and paid during the period were $100,000. Additional salaries and wages accrued at year end were $4,000. 

d. The amount of expense and expenditure to be recognized differs in more than one of these situations.