5. A marketing firm that markets refrigerators is interested in studying consumer behavior in the context of purchasing a particular brand of refrigerator. It wants to know, in particular, whether the income- level of the consumers inuences their choice of refrigerator brand. Currently there are three brands available in the marketplace. Brand A is a premium brand, Brand B is a more moderately priced brand, and Brand C is the most economical brand. A representative stratified random sampling procedure was adopted covering the entire market using income as the basis of selection. Income was classied into three categories: lower, middle and high. A sample of 200 consumers participated in this study and produced the following data: Brand A Brand B Brand C Lower 20 30 50 Middle 20 25 15 High 10 15 15 At the 5% signicance level, can it be concluded that there is a relationship between income-level and brand preference? Formulate and test the appropriate hypotheses. Use the critical value approach. Clearly state and explain your conclusion within the context of the