If a firm drops a product line, it will lose the revenue from that product. This loss is controllable and direct with respect to the decision to keep or drop the product. Dropping a product might also affect the sales of the firm's other products. Give two examples-one where the spillover effect increases the revenue from other products and one where the spillover effect decreases the revenue from other products. Are these spillover effects controllable and direct to the decision to drop the product?