25. Refer to the previous exercise. Repeat for the following scenarios:

a) A principal in a large high school is interested in student attitudes toward a proposed general achievement test to determine whether a student should graduate. She lists all of the first-period classes, assigning a number to each Then. using a random number table, she chooses a class at random and interviews every student in that class about the pro- posed test

b) A new restaurant opened in January. In June, after six months of operation, the owner applied for a loan to improve the building. The loan applicatiou requested au estimate of the yearly gross income of the business. The owner's record book contains receipts for cach day of operation since opening. She decided to calculate the average daily receipt based on a sample of the daily records and multiply that by the number of days of opera-tion in a year. She took a systematic saruple, with k = 7. sampling every Friday's record. The average daily receipt for this sample was then used to estimate the yearly receipts.