Question 2. Answer all parts. John and Jane were considering the time they were spending online in front of the computer during the lock down period. For a few weeks Jane collected data on the time they had spent online and found that the sample mean was 15hrs per day with the standard deviation of 20hrs. Jane wanted to know what the other students at her university were doing with regards to time spent online per day She asked a random sample of students from her university (population) and recorded the data which is shown below. Jane wanted to know the answers to question a) to c). John stated that Jane can only carry out the calculation below if she assumes the online time were following a normal distribution 5FNCE004W IAT/Semester 1 2021-22 Page 2 of 6 a) A sample of 60 students is drawn from a population. Calculate the point estimate and the 95% confidence interval for the population mean If the sample size were 17, find the new confidence interval and comment on it. Explain what these results mean and discuss if John's assumptions are correct (20 marks) Covid-19 cases in the news were also increasing during the lockdown period, hence the calls for ambulances. So, John decided to gather data about ambulances calls from a nearby ambulance station and found the data below b) An ambulance station receives, on average, twelve emergency calls over an eight-hour period. What is the probability of no emergency calls in a 15-minute period? (10 marks) Finally, the chances (probability) associated with the normal distribution table are given below so find the relevant values. When you get the answer explain what it means to someone who has not attended a statistics module. 1 c) For the standard Normal variable z, find: i. Pr(z>1.28) ii Priz>-1.64) ill Pr(-2