Wenton Powersports produces dune buggis. They have three assembly lines, "Razor," "Blazer," and "Tracer," named after the particular dune buggy models produced on those lines. Each assembly line was originally designed using the same target production rate. However, over the years, various changes have been made to the lines. Accordingly, management wishes to determine whether the assembly lines are still operating at the same average hourly production rate. The accompanying table shows a portion of the production data (in dune buggies/hour) for the last eight hours. (You may find it useful to reference the Etable.)