Identify which type of adjustment is indicated by these transactions. Choose accrued revenue, accrued expense, deferred revenue, deferred expense, or estimate.

utilities owed but not paid Blank $1$

cash received in advance for future services Blank $2$

supplies inventory purchased Blank $3$

fees earned but not yet collected Blank $4$

depreciation expense recorded Blank $5$

insurance paid for future periods Blank $6$