1. In the experiment of A and B consumers, 20 sample points are set for A consumers, and t he average value of word-of-mouth is 10.1 with a variance of 2.2; 19 sample points are set for B consumers,...

Extracted text: 1. In the experiment of A and B consumers, 20 sample points are set for A consumers, and t he average value of word-of-mouth is 10.1 with a variance of 2.2; 19 sample points are set for B consumers, and the average value of word-of-mouth is 10.9 with a variance of 2.7. Co mpare whether there is significant difference between the average word-of-mouth of A and B consumers. (a=0.05) (10')