Please help me solve these problems. Thank you.

18) Three companies (A, B, and C) are to be ranked first, second, and third in a list of companies with the highest customer satisfaction. a. List all the possible sets of rankings for these top three companies. b. Assuming that all sets of rankings are equally likely, what is the probability that Company A will be ranked first, Company B second, and Company C third? c. Assuming that all sets of rankings are equally likely, what is the probability that Company B will be ranked first? 19) One year, the distribution of salaries for professional sports players had mean $1.6 million and standard deviation $0.8 million. Suppose a sample of 400 major league players was taken. Find the approximate probability that the average salary of the 400 players that year exceeded $1.1 million. 20) The table shows the number of each type of book found at an online auction site during a recent search. Typeorsook Children's 51,033 Fiction 141,114 Nonfiction 253,074 Educational 67,252 a. Construct a relative frequency table for the book data. b. Construct a pie chart for the book data. 18) 19) 20) 16) Sales of a new line of athletic footwear are crucial to the success of a newly formed 16) company. The company wishes to estimate the average weekly sales of the new footwear to within $150 with 99% reliability. The initial sales indicate that the standard deviation of the weekly sales figures is approximately $1550. How many weeks of data must be sampled for the company to get the information it desires? 17) 17) C B M For the distribution drawn here, identify the mean, median, and mode