6. A manager of a small store wanted to discourage shoplifters by putting signs around the store saying: "Shoplifting is a crime!" However, he wanted to make sure that this sign would not cause customers to buy less. To test his research hypothesis that customers would not buy less, he displayed the signs every other Wednesday for $ weeks, for a total of 4 days displayed. He recorded the store's sales for those four Wednesdays, and then recorded the store's sales for the four alternate Wednesdays, when the signs were not displayed. On the Wednesdays with the sign, the sales were 83, 73, 81, and 79. On the Wednesdays without the sign, sales were $4, 90, 82, and 84. Do these results suggest that the general population of customers do not buy less when the signs are displayed? Use the .05 significance level. Note: Pay attention to the wording in this question when formulating your hypotheses and conclusions! a) Use the four steps of hypothesis testing b) Illustrate the distributions involved c) Calculate the effect size of this study