please help with the multiple choice questions 3,4 and 5

Question 3: A company has a unit contribution margin of $5,000, total sales in June are estimated at $900,000 and fixed costs are \$600,000. How many units must be sold to attain net operating inceme of $150,000 ? a. 30 units b. 120 units c. 130 units d. 150 units. e. 180 units Question 4: JOLO Ine sells one product for 5150. Unit fixed cost is $25 and unit variable cost is $90. Net operating inceme increases by what amount if ONE more anit is sold? a. $150 b, $125 c. 560 d. 535 e. Not enough information to determine. Question 5; McGovern Construction is looking to calculate its margin of safety on its dump trucks. The CFO put together a list of items that might be relevant to the calculation: 1. Price per truck: $120,000 2. UCM per truck: $15,000 3. Variable selling costs related to dump trucks: $5,500 4. Actual sales: $3,600,000 5. Fixed costs: $1,000,000 Which of the following is not relevant for calculating margin of safety? a. UCM per truek b. Variable selling cost related to dump trucks. c. Fixed costs d. Actual sales