R R Graphics: Device 2 (ACTIVE) R R Graphics: Device 2 (ACTIVE) X CO frequency 0.09 30 aby 0.07 O 0.04 0.06 0.08 0.10 0 0 09 00000 0.05 abv -2 -1 0 2 norm quantilesR R Graphics: Device 2 (ACTIVE) X R R Graphics: Device 2 (ACTIVE) 110 115 10 15 20 25 GPS AVERAGE frequency 100 105 LO O -2 -1 0 2 100 105 110 115 norm quantiles GPS AVERAGEFinish the following questions using R and R commander. Make sure that you copy and paste the computer outputs into the space below each question and write down your answers in statements. Graphs should include titles and axis labels, as appropriate. 1. For the following variables of interest, i) Use R to create a normal probability plot and a histogram. Paste your work into your report ii) Describe your ndings. In particular, do the graphs provide evidence against the assumption of a normally distributed population? iii) Based on your descriptions (as well as the sample size n), determine if one mean inference is valid, and whether z-procedures or t-procedures should be employed. For each dataset, you may assume the data are obtained via random sampling and that the population standard deviation is unknown. a) The dataset "Beer2 1.xlsx" contains information regarding a sample of 2 1 beers brands in the United States. The variable of interest is abv (alcohol by volume) for the beer brands. (3 marks) b) The dataset"SchoollOO.1dsx" contains information regarding a sample of 100 schools from the Great Britain. The variable of interest is GPS_AVERAGE (average reading scores on an aptitude test for students at that school). (3 marks) c) In the above work, we did not examine the boxplots for the considered samples. What can a boxplot show us that cannot be seen in a normal probability plot or histogram? (2 marks)