Description

Use the Cars data set in the SP4R library to complete this exercise.

1. Creating a New Data Set Variable
a. Create a new variable called mpg_average in the Cars data set. This new variable should simply be the average gas mileage between mpg_city and mpg_highway.
b. Print the first five observations for the variables mpg_city, mpg_highway, and mpg_average to ensure that the new variable is created.