16. In anticipation of a lunchtime rush, a small cafe has made seven egg-salad sandwiches, five tuna sandwiches, and six ham sandwiches, along with nine garden salads and six Caesar salads. In how many ways can this food be displayed in a single row on the counter? 17. Nick is responsible for keeping the office cooler filled with drinks. He can purchase up to six cases of carbonated drinks, four cases of juices, five cases of spring water, and five cases of iced tea without sending the purchase order to his supervisor for approval. How many different purchases can Nick make without his supervisor's signature? 18. Veronica finds eight sweaters she likes on sale in a store. How many different sets of sweaters could she choose if money is no object