Unit 1 Permutations Show all your answers asap please

8. Five students are asked to secretly choose a number from 1 to 12, a) Determine the probability, to three decimal places, that no two students choose the same number. [3] b) Determine the probability, to three decimal places, that at least two students choose the same number. [2] 5. Maxine is arranging textbooks on her bookshelf. She has 3 math textbooks, 2 physics textbooks, 1 English textbook and 1 biology textbook. How many ways can these books be arranged if the math textbooks are side by side and the physics textbooks are also side by side on the shelf. [3]