i am confused on how to do this hw question? if someone can offer a step by step explanation that would be great!

Cullumber provides environmentally friendly lawn services for homeowners. Its operating costs are as follows. Cullumber charges $85 per treatment for the average single-family lawn. For the month ended July 31,2022 , the company har sales of $10,200 CULLUMBER CVP Income Statement Contribution Margin Selling Expenses Net Income/(Loss) Administrative Expenses Gross Profit Cost of Goods Sold Variable Costs Sales Fixed Costs Total $ $ Per Unit Percent of Sales