Please help me with the questions below:

btw its #28 not 18

2T. Nguyen Corporation has provided the following contribution format income statement. Assume that the following information is within the relevant range. Sales {3,000 units} $ 120,000 Variable expenses 90,000 Contribution margin 30,000 Fixed expenses 21,000 Net operating income $ 9,000 If sales decline to 2,900 units, the net operating income would be closest to: A} $29,000 B) $1,000 C} $8,100 D} $8,000 28. Stockmaster Corporation has provided the following contribution format income statement. Assume that the following information is within the relevant range. Sales (8.000 units} $ 320,000 Variable expenses 192,000 Contribution margin 123,000 Fixed expenses 121,600 Net operating income $ 6,400 The margin of safety in dollars is closest to: A} $6,400 B} $16,000 C) $121,600 D} $128,000 29. Using the data contained above in #13 regarding Stockmaster Corporation write in the 1iralue percentage to use for Sales on the asset sheet