Having a hard time understanding the Perpetual inventory system in these cases!

1. Sold merchandise costing $4,500 for $1,000 cash and $7,000 on open account.

2. Purchased land and building for $100,000 cash and a $300,000 mortgage. The land was recently appraised at $60,000 and the building at $340,000.

Finally,

3. Declared a cash dividend totaling $13,500. The dividend will be paid in six weeks.

1. Debit Cash for 1,000
Debit Accounts Receivable for 7,000
Credit Sales Revenue for 8,000
(to record the sale of merchandise)

Debit Cost of Goods Sold for 4,500
Credit Merchandise Inventory for 4,500
(to record the cost of merchandise that was sold)

2. Debit Land for 60,000
Debit Building for 340,000
Credit Cash for 100,000
Credit Mortgage Payable for 300,000
(to record the purchase of land and building)

3. Debit Retained Earnings for 13,500
Credit Cash Dividends Payable for 13,500
(to record cash dividends declared)

When dividends are paid you will have the following journal entry:
Debit Cash Dividends Payable for 13,500
Credit Cash for 13,500
(to record payment of cash dividends declared)