The American Beef Growers Association is trying to promote the consumption of beef products. The organization performs numerous studies, the results of which are often used in advertising campaigns. One such study involved a quality perception test. Three grades of beef were involved: choice, standard, and economy. A random sample of people was provided pieces of choice-grade beefsteak and was asked to rate its quality on a scale of 1 to 100. A second sample of people was given pieces of standard-grade beefsteak, and a third sample was given pieces of economy-grade beefsteak, with instructions to rate the beef on the 100-point scale. The following data were obtained:

Choice Standard Economy 78 67 65 87 80 62 90 78 70 87 80 66 89 67 70 90 70 73

a. What measurement level do these data possess?
Would it be appropriate to assume that such data could be obtained from a normal distribution?
Explain your answers.

b. Based on the sample data, what conclusions should be reached concerning the median quality perception scores for the three grades of beef?
Test using an a  0.01.