After the success of the company's first two months, Santana Rey continues to operate Business Solutions. The November $30,2020,$ unadjusted trial balance of Business Solutions $($reflecting its transactions for October and November of $2020)$ follows.

$\backslash$table$[[$Number$,$Account Title,Debit,Credit$],[101,$Cash,$$38,864,],[106,$Accounts receivable,$13,118,],[126,$Computer supplies,$2,645,],[128,$Prepaid insurance,$2,040,],[131,$Prepaid rent,$2,920,],[163,$office equipment,$8,700,],[164,$Accumulated depreciation$-$office equipment,,$$0$

Business Solutions had the following transactions and events in December $2020.$

December $2$ Paid $$970$ cash to Hillside Mall for Business Solutions's share of mall advertising costs.

December $3$ Paid $$460$ cash for minor repairs to the company's computer.

December $4$ Received $$4,750$ cash from Alex's Engineering Co$.$ for the receivable from November.

December $10$ Paid cash to Lyn Addie for six days of work at the rate of $$115$ per day.

December $14$ Notified by Alex's Engineering Company that Business Solutions's bid of $$7,800$ on a proposed project has been accepted. Alex's paid a $$2,000$ cash advance to Business Solutions.

December $15$ Purchased $$1,600$ of computer supplies on credit from Harris office Products.

December $16$ Sent a reminder to Gomez Company to pay the fee for services recorded on November $8.$

December $20$ Completed a project for Liu Corporation and received $$5,675$ cash.

December $22-26$ Took the week off for the holidays.

December $28$ Received $$3,600$ cash from Gomez Company on its receivable.

December $29$ Reimbursed S$.$ Rey for business automobile mileage $(500$ miles at $$0\mathrm{.}31$ per mile$).$

December $31$ The company paid $$1,100$ cash in dividends.

The following additional facts are collected for use in making adjusting entries priono preparing financial statements for the company's first three months.

a$.$ The December $31$ inventory count of computer supplies shows $$650$ still available.

b$.$ Three months have expired since the $12-$month insurance premium was paid in advance.

c$.$ As of December $31,$ Lyn Addie has not been paid for four days of work at $$115$ per day.

d$.$ The computer system, acquired on October $1,$ is expected to have a four$-$year life with no salvage value.

e$.$ The office equipment, acquired on October $1,$ is expected to have a five$-$year life with no salvage value.

f$.$ Three of the four months' prepaid rent have expired.

Required:

Prepare journal entries to record each of the December transactions and events for Business Solutions.

$2-$a$.$ Prepare adjusting entries to reflect a through $f.$

$2-$b$.$ Post the journal entries to record each of the December transactions from Requirement $1$ and adjusting entries from Requirement $2$A$.$ After completing Requirement $7,$ post the closing entries to the general ledger accounts.

Prepare an adjusted trial balance as of December $31,2020.$