A taste test is conducted to rate consumer preference between brands C and P of a popular soft drink. In addition, the age of the respondent is recorded (1 = less than 20,2 = 20 or more). Preference...

A taste test is conducted to rate consumer preference between brands C and P of a popular soft drink. In addition, the age of the respondent is recorded (1 = less than 20,2 = 20 or more). Preference data (on a scale of 1-10) is as follows:

(a) Write a SAS program to analyze these data with a two-way analysis of variance. (Careful: Is the design balanced?) Note: Go ahead and treat these data as interval data even though some analysts would prefer that you use a nonparametric analysis.

(b) Use SAS to plot an interaction graph.

(c) Follow up with a t-test comparing brand C to brand P for each age group separately.