Question 4 (Distribution Parameters, Special Distributions) An environmental engineer has been contracted to undertake six independent measurements (at different locations) of heavy metal concentrations in a local water supply and has obtained the following raw data: | Location | 1 | 2 | 3] 4]5]6 | a) Calculate the sample average concentration (X) and sample standard deviation (s) of this data. (2 marks) b) If it is known that independent measurements X of this water supply follow a Normal distribution with mean of 0.5 g L~! and standard deviation of 0.1 g L=, caleulate the probability of observing a value of the sample average greater than the value of X you obtained in a). (2 marks)