please answer A , B, C

(b) Four customers purchased desktop computers in 2011. What is the probability that all of the computers have Company X's chips? (0) Which changed more from 201 O to 2011: the probability of one customer purchasing a desktop computer with Company X's chip or the probability of four customers all purchasing desktop computers with Company X's chips? Companies X and Y compete to put their processing chips into personal computers. In 2011, Company X claimed 68% of the laptop market and 81% of the market for desktop computers. In 2010, Company X commanded 84% of the laptop market and 56% of the desktop market. Complete pans (a) through (9) below. (a) What is the probability that someone who bought a laptop in 2010 and again in 2011 purchased computers with Company X's chips? Identify any assumptions needed for your answer. Assuming the events are 7 the probability is (Round to three decimal places as needed.)