Classify the following adjusting entries as involving prepaid expenses(PE), unearned revenues)UR), accrued expenses(AE), or accrued revenues(AR).

a. ____ to record revenue earned that was previouslu received as cash advance.
b.___ to record annual depreciation expense.
c. to record wages expense incurred but not yet paid(nor recorded).
d. to record revenue earned but not yet billed
e. to record expiration of paid insurance.