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Question 2 The telephone lines serving Oman Air reservation office are all busy about 60% of the time. (a) If you are calling this office, what is the probability that you will complete your call (the office will answer your call) on the first try or the second try? (b) If you and a friend must both complete calls to this office, what is the probability that a total of five tries will be necessary for both of you to get through? Question 3 The exam scores of a math assessment test at a college are normally distributed with mean 78.7 and a standard deviation of 5.6. If you know that grade A is given for scores above 90, and grade F is given for scores less than 50, find the following: (a) What is the probability that a randomly selected student got grade A? (b) What is the score that 70% of the students could not reach it? Question 4 Among a large number of applicants for a certain position in a company, 40% have a degree in business management, 35% have a degree in economics, and 25% have a degree in accounting. If 6 applicants are selected to be interviewed, find the following probabilities. (a) 2 applicants from each group are interviewed. b) At least 1 applicant has a degree in business management is interviewed. (c) If the company manager wants to be 99% confident that at least 1 applicant with a degree in economics will be interviewed, how many total applicants he should interview