1. Suppose there are 12 books consisting of 5 dictionaries, 3 mathematics books, and 4 science books. How many ways can these 12 books be arranged in a bookshelf? 2. How many ways can seven persons be seated in a theater? 3. Adrian has 10 shirts in his closet. He wants to choose five shirts to bring for an out-of- town trip. How many ways can he choose the shirts? 4. In a beauty contest, there are five semifinalists from which three winners will be chosen. How many ways can the winners be chosen? 5. A family with six members sit in a round table for dinner. How many ways can the members of the family be seated? 6. A salad bar offers eight choices of toppings for lettuce. In how many ways can you choose four toppings