Shamrock Windows manufactures and sells custom storm windows for three-season porches. Sharnrock also provides installation service for the windows. The installation process does not involve changes in the windows, so this service can be performed by other vendors. Shamrock enters into the following contract on July 1,2020, with a local homeowner. The customer purchases windows for a price of $2,360 and chooses Shamrock to do the installation. Shamrock charges the same price for the windows irrespective of whether it does the installation or not. The customer pays Shamrock $1,920 (which equals the standalone selling price of the windows, which have a cost of $1,100 ) upon delivery and the remaining balance upon installation of the windows. The windows are delivered on September 1,2020, Shamrock completes installation on October 15,2020 , and the customer pays the balance due. (a) Shamrock estimates the standalone selling price of the installation based on an estimated cost of $440 plus a margin of 20% on cost. Account Titles and Explanation Debit Credit 5020 NoEntry Notntry (To record contract entered into) .2020 Canh 1920 Nccounts Reccivable 4%0 Sales Reverue Unearned Ssles Revenue (To record sales) Cost of Goods Sold 1100 Inventory 1100 (To record cost of goods sold) 5,2020 Cash 440