Speedy Supplies sells a product at a price of $110.00. It's variable manufactured cost is $30.00 and the variable marketing cost per unit is $10.50 with fixed cost per period of $70,000. What would be the change in operating income under variable costs if sales increase from 7,000 to 7,900 units? O A. Loss of $7,450 OB. $72,000 O C. $62,550 OD. $89,550