please help me with this 3.1

cobo/Documents/APS15M1%20Exam%202021.pdf Degree and Diploma Examinations: JULY 2021 APS11M1/15M1/APS16M1 Applied statistics I Final Examination Page 4 of 6 on 3 Once a week a merchandiser replenishes the stocks of a particular product brand in the six stores for which she is responsible. Experience has shown that there is one in five chance that a given store will have run out of stock before the merchandiser's weekly visit. a) Which probability distribution is appropriate in this problem and why? b) What is the probability that, on a given weekly round, the merchandiser will find exactly one store out of stock? c) What is the probability that the most two stores will be out of stock? d) What is the mean number of stores out of stock each week? 3.2. Airline passengers arrive randomly and independently at the passenger screening facility at a major international airport. The mean arrival rate is 10 passengers per minute. a) Calculate the probability of no arrivals in a one minute period. b) Calculate the probability of at least 3 arrivals in a one minute period. c) Calculate the probability of exactly 8 arrivals in a 15-second period. 3.3. The lifetime of a certain type of automatic washing machine is normally distributed with a mean of 3.1 years and a standard deviation of 1 1 years. al If this tone of machine is guaranteed for ane vear. what percentage of the 10:50 PM O HD