Critical Thinking In each of the following situations, the sampling frame does not match the population, resulting in undercoverage. Give examples of population members that might have been omitted.

(a) The population consists of all 250 students in your large statistics class.

You plan to obtain a simple random sample of 30 students by using the sampling frame of students present next Monday.

(b) The population consists of all 15-year-olds living in the attendance district of a local high school. You plan to obtain a simple random sample of 200 such residents by using the student roster of the high school as the sampling frame.