show work please

a) what is the gross margin?

b) if Wayne had a $5000 increase in sales, profit sould increase by?

.. $70,000 Presented is information from Wayne's contribution income statement: Sales.... Less variable costs: Manufacturing Selling and administrative Contribution margin... Less fixed costs: Manufacturing Selling and administrative Profit...... $20,000 10,000 (30,000) 40,000 . 15,000 8,000 (23,000) $17,000