Prepare the journal entries for each transaction.

Post to the ledger and prepare a trial balance.
May 2 Purchased merchandise on account from Wendy Supply Co. P10,000 terms, 2/10,n/30
3 Sold merchandise for P4,500 terms P500 down balance 2/10,n/30.
4 Paid P500 cash for freight on May 3 sales.
5 Received credit from Wendy for merchandise returned.P800.
6 Made partial payment to Wendy P5,000.
7 Received partial collection from customer on account date May 3 P3,000
8 Paid Wendy's account in full.
9 Received collections in full from customer billed on May 3
10 Cash purchases of merchandise P6,800
11 Received refund from supplier for cash purchase of April 16 P500
12 Purchased merchandise from KFC Enterprise, P14,000 terms 2/10,n/30

To prepare the journal entries for each transaction, here are the steps:

1. May 2: Purchased merchandise on account from Wendy Supply Co. P10,000 terms 2/10, n/30
- Debit: Merchandise Inventory (P10,000)
- Credit: Accounts Payable (P10,000)

2. May 3: Sold merchandise for P4,500 terms P500 down balance 2/10, n/30.
- Debit: Accounts Receivable (P4,500)
- Credit: Sales Revenue (P4,500)
- Debit: Cost of Goods Sold (P3,500)
- Credit: Merchandise Inventory (P3,500)

3. May 4: Paid P500 cash for freight on May 3 sales.
- Debit: Freight Expense (P500)
- Credit: Cash (P500)

4. May 5: Received credit from Wendy for merchandise returned. P800.
- Debit: Accounts Payable (P800)
- Credit: Merchandise Inventory (P800)

5. May 6: Made partial payment to Wendy P5,000.
- Debit: Accounts Payable (P5,000)
- Credit: Cash (P5,000)

6. May 7: Received partial collection from customer on account date May 3 P3,000.
- Debit: Cash (P3,000)
- Credit: Accounts Receivable (P3,000)

7. May 8: Paid Wendy's account in full.
- Debit: Accounts Payable (P5,200)
- Credit: Cash (P5,200)

8. May 9: Received collections in full from customer billed on May 3.
- Debit: Cash (P4,185) [P4,500 - P315 (P4,500 * 10%)]
- Credit: Accounts Receivable (P4,500)
- Debit: Sales Discount (P315) [P4,500 * 10%]

9. May 10: Cash purchases of merchandise P6,800.
- Debit: Merchandise Inventory (P6,800)
- Credit: Cash (P6,800)

10. May 11: Received refund from supplier for cash purchase of April 16 P500.
- Debit: Accounts Payable (P500)
- Credit: Cash (P500)

11. May 12: Purchased merchandise from KFC Enterprise, P14,000 terms 2/10, n/30
- Debit: Merchandise Inventory (P14,000)
- Credit: Accounts Payable (P14,000)

To post the journal entries to the ledger and prepare a trial balance, you will need to record the above journal entries in the respective ledger accounts (Accounts Receivable, Accounts Payable, Sales Revenue, etc.) and then prepare a trial balance by listing all the ledger account balances. However, since the question does not provide the existing balances of the ledger accounts, it is not possible to prepare a complete trial balance.

To prepare the journal entries for each transaction, follow these steps:

1. Identify the accounts involved in each transaction and determine the account type (assets, liabilities, equity, revenue, or expenses).

2. Determine if the accounts are increasing (+) or decreasing (-) based on the nature of the transaction.

3. Use the double-entry bookkeeping system to record the transactions. Debit the accounts that are increasing and credit the accounts that are decreasing.

4. Include the date and a brief description of the transaction in the journal entry.

Here are the journal entries for the given transactions:

May 2:
Purchased merchandise on account from Wendy Supply Co.
Debit: Merchandise (Inventory) - P10,000
Credit: Accounts Payable - P10,000

May 3:
Sold merchandise for P4,500 terms P500 down balance 2/10,n/30.
Debit: Accounts Receivable - P4,500
Credit: Sales Revenue - P4,500

Received credit from Wendy for merchandise returned.P800.
Debit: Accounts Payable - P800
Credit: Merchandise Returns and Allowances - P800

May 4:
Paid P500 cash for freight on May 3 sales.
Debit: Freight Expense - P500
Credit: Cash - P500

May 5:
Made partial payment to Wendy P5,000.
Debit: Accounts Payable - P5,000
Credit: Cash - P5,000

May 7:
Received partial collection from customer on account dated May 3 P3,000.
Debit: Cash - P3,000
Credit: Accounts Receivable - P3,000

May 8:
Paid Wendy's account in full.
Debit: Accounts Payable - P5,000
Credit: Cash - P5,000

May 9:
Received collections in full from customer billed on May 3.
Debit: Cash - P1,500 (P4,500 - P3,000)
Credit: Accounts Receivable - P1,500

May 10:
Cash purchases of merchandise P6,800.
Debit: Merchandise (Inventory) - P6,800
Credit: Cash - P6,800

May 11:
Received refund from supplier for cash purchase of April 16 P500.
Debit: Cash - P500
Credit: Accounts Payable - P500

May 12:
Purchased merchandise from KFC Enterprise, P14,000 terms 2/10,n/30.
Debit: Merchandise (Inventory) - P14,000
Credit: Accounts Payable - P14,000

After preparing the journal entries, you can post them to the ledger by transferring the debit and credit amounts to the respective accounts. Once all transactions are posted, you can prepare a trial balance by listing all the accounts and their balances to ensure that debits equal credits.