an advertising agency is testing the effectiv...
an advertising agency is testing the effectiveness of a new commercial. they are trying out the commercial in three different time lengths (15, 30, and 60 seconds) and two formats (animated vs. live action). each test audience will rate the product after seeing the commercial shown in one way. what is a description of this study? choose the correct answer below. a. an experiment with 1 factor (length) blocked by format with 3 levels (15, 30, 60). b. an experiment with 2 factors (length and format), at 5 levels (15, 30, 60, animated, and live action) for 5 treatments. c. a sample stratified by length and format. d. an experiment with 2 factors (length and format), one having 3 levels (15, 30, 60) and the other having 2 levels (animated and live action) for 6 treatments.