A study investigated the effect of the length and the repetition of TV advertisements on students' desire to eat at a Sub-U-Like sandwich franchise. Sixty students watched a 50-minute television program that showed at least one commercial for Sub-U-Like during advertisement breaks. Some students saw a 30-second commerical, some saw a 60-second commercial, others a 90-second commerical. The same commerical was shown one, three, or five times during the program. After the viewing, each student was asked to rate their craving for a Sub-U-Like sandwich from the set {"Don't want to eat", "Neutral", "Want to eat"}.

(a) What kind of study is this?
A. An experiment because the study investigator compared the degree of craving between different amounts of exposure to advertisements in the study.
B. An observational study because there was no control group.
C. An observational study because the study investigator observed the students’ ratings on their craving for the Sub-U-Like sandwich.
D. An experiment because the study investigator controlled the amount of exposure to advertisements the participating students received.


(b) What is/are the response variable(s) in the "Sub-U-Like" study?
A. The 50-minute television program
B. The length and repetition of the TV advertisements
C. Craving for Sub-U-Like
D. The 60 students
E. One, three, or five commercials during the 50-minute television program


(c) If the investigator would like to compare the distributions of the response variable across different lengths and frequencies of commercials, which of the following displays is appropriate?
A. Scatter plot
B. Side-by-side boxplots
C. Histogram
D. Contingency table
E. Stem-and-leaf plot


(d) What is/are the factor(s) in the "Sub-U-Like" study?
A. One, three, or five commercials during the 50-minute television program
B. Length and frequency of the commercial.
C. 30-second, 60-second and 90-second commercials
D. The length of the television program
E. Craving for Sub-U-Like
F. The number of students


(e) How many treatments are there in the "Sub-U-Like" study?
Enter your answer as a number (e.g. 1), not as text.
Answer: