Current Attempt in Progress Crane Window Cleaners' monthly Income statement at several levels of activity is as follows: Windows washed 2,500 4,200 7,000 Sales revenue $3,800 $6384 $ 11,856 Cost of goods sold 1,400 2,352 4,368 Gross pront 2,400 4,032 7,483 Operating expenses Advertising expense 400 400 400 Salaries and wages expense 750 920 1,280 Insurance expense 200 200 200 Postage expense 450 756 1,404 Total operating expense 1800 2276 3,284 Operating Income 600 $1756 $ 4204 (a) identify each expense as foed, varlable, or mixed Cest of goods sold variable Advertising expense fd Salaries and Wages expense mboid v Insurance expende Postage expense variat (b) Prepare a contribution margin income statement based on a volume of 7.900 windows (Round unit cost to 2 decimal places, ea 52.75 and all other answers to O decimal places, 5,275) 7,900 wodow Per Unit 5214 Gen Topol Spotify Rocket Come (b) Prepare a contribution margin income statement based on a volume of 7,900 windows. (Round unit cost to 2 decimal places, eg. 52.75 and all other answers to O decimal places, e.g. 5,275.) Sales Revenue Variable Expenses Cost of Goods Sold 14141 Salaries Expense Postage Expense Total Variable Expenses Contribution Margin Fixed Expenses Advertising Expense Salaries Expense Insurance Expense Total Fixed Expenses Operating Income $ 7,900 windows 5214 Per Unit 66 E 179