please show steps to get answer D

Sale price per unit Direct materials used Direct labor incurred Variable manufacturing overhead Variable selling and administrative expenses Fixed manufacturing overhead Fixed selling and administrative expenses Units produced and sold $50.00 $16,400 $187,000 $123,000 $71,000 $65,000 $12,000 24,000 Assume no beginning inventory Assuming there is excess capacity, what would be the effect on operating income of accepting a special order for 3,400 units at a sale price of $42 per product assuming additional fixed manufacturing overhead costs of $5,000 is incurred? (NOTE: Assume regular sales are not affected by the special order. Round any intermediary calculations to the nearest cent.) A. Increase by $142,800 B. Decrease by $81,496 C. Increase by $86,496 D. Increase by $81,496