Modern Machine Shop $($MMS$)$ Inc. manufactures special moulds that are used in the production of plastic toys. Below is MMS$$s accounts receivable ledger from October $1$ to December $31,$ current year:

General Ledger Accounts Receivable

Date Explanation Debit Credit Balance

Sept. $30$ Balance $12,700$

Oct. $8$ Wrote off uncollectible accounts. $3,1009,600$

Oct. $15$ Sold $10$ moulds to Allen Inc. $21,00030,600$

Oct. $31$ Sold $15$ moulds to Machinex Ltd$.23,50054,100$

Nov. $5$ Received the amount due from Machinex for moulds purchased on October $31.23,50030,600$

Nov. $7$ Sold $20$ moulds to Centra Corp. $42,00056,600$

Nov. $29$ Centra Corp. made a partial payment on the moulds purchased on November $7.21,00035,600$

Dec. $20$ Recovered $$2,100$ that was written off on October $8.2,1002,10035,600$

Additional information is as follows:

MMS sold its special moulds at $$2,100$ each.

All sales were on credit with terms, n$/30.$

MMS$$s records included the following items and their balances as at September $30,$ current year:

Net sales $ $260,000$

Accounts receivable $12,700$

Allowance for doubtful accounts $($credit balance$)2,900$

Required:

$1.$ Prepare the journal entries to record the transactions on October $8,$ November $5,$ and December $20.($If no entry is required for a transaction$/$event$,$ select $"$No journal entry required" in the first account field.$)$