A sample of 100 call interarrival times (in seconds) at a call-center was collected for use in a simulation study. The summary information for this data is as follows: Observation type Number of observations Minimum observation Maximum observation Mean Median Variance Coefficient of variation Skewness Real valued 100 2.81597 14.22427 11.23158 11.56637 4.23805 0.18329 -1.73786 (a) Hypothesize a probability distribution for this data based on the above summary. Be as specific as possible (eliminate as many alternatives as possible with explanations). (b) Sketch the probability density function of the hypothesized distribution. (c) Construct a 90% confidence interval for the sample mean. (d) Test the null hypothesis that the population mean is 10.