1. A sample of 4 mousetraps taken from a batch of 100 mousetraps is to be inspected. How many dierent sets of samples could be selected? 2. A volleyball team has 12 members, one coach, and 2 managers. How many different combinations of 7 people can be chosen to kneel on the front row of the team picture? 3. In a group of 10 people, each person shakes hands with everyone else once. How many handshakes are there? 4. You can order a hamburger with cheese, onion, pickle, relish, mustard, lettuce, tomato, or mayonnaise. How many different combinations of the \"extras\" can you order, choosing any four of them? 5. A school club has 15 boys and 16 girls as members. How many different 6-person committees can be selected from the membership if equal numbers of boys and girls are selected? 6. The junior and senior class councils each have 10 members. In how many ways can a prom committee be formed if it is to consist of 3 seniors and 2 juniors selected from the two class councils