Suppose the duration of your phone calls follows a distribution with mean of 2.8 minutes and standard deviation of 2.1 minutes. From a random sample of n = 45 calls, your parents computed a sample mean of 3.4 minutes and a sample standard deviation of 2.9 minutes. a. What are its mean and standard deviation? b. What are the mean and standard deviation of the data distribution? c. Find the mean and standard deviation of the sampling distribution of the sample mean. d. What is the probability to obtain a sample mean larger than 3.5 minutes?