Please solve the incorrect answers! Idk what I did wrong

Exercise 3.27 Stellar produces one single product, a small reading tablet, and sells it at $130 per unit. Its current annual sales are $312,000. Its annual fixed costs include factory rent, 562,400; depreciation expense; equipment, $15,600; utilities, $31,200; insurance, $12,480. Its variable costs include materials, $39 per unit, and direct labour, $52 per unit. Stellar's income tax rate is 20%. Your answer is correct. What is the contribution margin per unit? Contribution margin per unit SHOW SOLUTION SHOW ANSWER LINK TO TEXT LINK TO TEXT LINK TO TEXT Your answer is correct. What is the contribution margin ratio? Contribution margin ratio 30. SHOW SOLUTION SHOW ANSWER LINK TO TEXT LINK TO TEXT LINK TO TEXT x Your answer is incorrect. Try again. How many units must Stellar sell to break even? (Round answer to the next whole integer, e.g. 1,255.) Sales 2320 units LINK TO TEXT LINK TO TEXT LINK TO TEXT x Your answer is incorrect. Try again. If Stellar would like to earn a profit after tax of $16,000, what should the sales be? At this sales level, what is the degree of operating leverage? What is the margin of safety in unit? (Round total sales and margin of safety to O decimal places, e.g. 5,125. Round degree of operating leverage to 2 decimal places, e.g. 15.16.) Total Sales 2371 Degree of operating leverage 46.24 Margin of safety 80 units LINK TO TEXT LINK TO TEXT LINK TO TEXT x Your answer is incorrect. Try again. If Stellar would like to earn a profit after tax that is 8% of sales, what should the sales be? How many units does Stellar need to increase from the current sales level? Total Sales 411190 Units to be increased by 99190 units LINK TO TEXT LINK TO TEXT LINK TO TEXT