A company markets its products by direct mail. An experiment was conducted to study the effects of three factors on the customer response rate for a particular product. The three factors are A = type of mail used (3rd class, 1st class), B = type of descriptive brochure (color, black-and-white), and C = offer price ($19.95, $24.95). The mailings are made to two groups of 8,000 randomly selected customers, with 1,000 customers in each group receiving each treatment combination. Each group of customers is considered as a replicate. The response variable is the number of orders placed. The experimental data is shown below.

g s OOHJONLh-FUJNH Number of Orders Coded Factors A B C Replicate l 50 44 + 46 + 42 + 49 + 48 + + 47 + + 56 Factor Levels Low (1) High (+1) A (class) 3rd 1st B (type) BW Color C ($) $19.95 $24.95 Replicate 2 54 42 48 43 46 45 48 54 Residuals vs. Run 3 1.5 Residuals 0 -1.5 -3 A 7 10 13 16 Run Number