In recent years, shopping malls have become a favorite site for companies to test consumers' responses to new products through interviews. These interviews, called "mall intercepts," have largely replaced door-to-door interviewing because they are relatively quick and inexpensive. Research has shown that 95% of American households shop at malls at least once a year and that two-thirds shop at malls at least once every 2 weeks. (a) Can consumers interviewed in this manner be considered a random sample of the population as a whole? Explain. (b) Is the sample a random sample of people who go to malls? Explain. (c) What about just for people who go to that mall? Explain.