The following is Porte Alegre Co.'s contribution format income statement for last month: Sales Variable expenses Contribution Margin Fixed expenses Net Operating Income $800,000 $300,000 $500,000 $400,000 $100,000 The Company has no beginning or ending inventories. The company produced and sold 10,000 units last month. If sales increase by 200 units, by how much should net operating income increase? $16,000 $5,000 O $2,000 $10.000