5.. Several experimental designs are described in Questions a through d. For each design answer the following questions: (1) What type of design is being used? Explain. ( 11) Diagrammatically represent the design. T ( 1 1 1 ) Discuss the threats to internal and external validity. for the design. a . A leading manufacturer of frozen food products decided to test the effectiveness of an in-store display. Four large supermarkets, located near the company's main office, were selected for the experiment. The display was set up in two of the stores and sales were monitored for a period of two weeks. The sales of the other two stores were also recorded but no displays were used. Sales volume for the frozen food products increased 2 percent more in the stores that used the in-store displays than in the stores that did not use the displays. b . A branch of Alcoholics Anonymous wanted to test consumer attitudes toward an anti-drinking advertisement. Two random samples of respondents in Piscataway, New Jersey, were selected for the experiment. Personal interviews, relating to consumer attitudes toward alcoholism, were conducted with both samples. One of the samples was shown the anti-drinking advertisement and following this, personal interviews were conducted with both samples in order to examine consumer attitudes toward alcoholism. C . A manufacturer of a line of office equipment, based in Houston, Texas, marketed its products in the southwest United States. The region consisted of 30 geographic divisions, each headed by a divisional manager who had a staff of salespeople. The firm's management wanted to test the effectiveness of a new sales training program in which the sales personnel in five of the divisions typically participated. The divisional managers of these five divisions were instructed to monitor sales for each salesperson for each of the five months before and after the training program. The results were to be sent to the vice-president of sales in Houston, who planned to compare them against sales changes in the other divisions. d. A new manufacturer of women's cosmetics was planning to retail the firm's products through mail-order. The firm's management was considering the use of direct mail advertisements to stimulate sales of their products. Prior to committing themselves to advertising through direct mail, management conducted an experiment. A random sample of 1: 000 housewives . was selected from