Billy's Window Co. opened for business on September 1, 2021. The following account balances existed:

Cash 85,192

Window Inventory (210 units @ $65/unit) 13,650

Building 52,500

Accounts Payable (Great Wattage) 13,650

Notes Payable 37,692

Common Stock (5,000 shares, $1 par) 80,000

Preferred Stock (200 shares, 5%, $10 par) 20,000

The following events and transactions occurred through December 31, 2021:

9/2 Signed a 10-month contract to provide windows to Construction Co. for $72,000, which was paid immediately. Work is to be performed equally each month.

9/3 Sold 35 windows to Repair Co. for $160.00 each, payment in cash.

9/4 Purchased 260 additional windows for its inventory, on account, for $23,500. Terms were 4/10, n/20.

9/7 Repair Co. returned 8 damaged windows, and received a refund.

QUESTION: How do I make the journal entries for these four transactions? (please provide detailed explanation so that I can understand it)