The following table contains 2 variables and 5 observations. a. Create a new variable called "Sum" that contains the sum of the values of x1 and x2 for each observation. What is the average value of Sum? Note: Round your answer to two decimal places. b. Create a new variable calied "Difference" that contains the absolute difference between the values of x1 and x2 for each observation. What is the average value of Difference? Note: Round your answer to two decimal places