Could you please help me understand how to get these answers, thank you

Net Income Planning Selected operating data for Oakbrook Company in four independent situations are shown below. Fill in the blanks for each independent situation. A B C D Sales $525,000 C. $ e. $300,000 Variable expense S a. $405,000 f. g. Fixed expense S b. $98,000 $47,000 $140,000 Net income (loss) before tax $22,000 $307,000 $28,000 $(20,000) Units sold 35,000 d. Unit contribution margin $8.25 $9.00 Contribution margin ratio 0.25 h