22. When the Yankelovich polling organization asked, "Should laws be passed to eliminate all possibilities of special interests giving huge sums of money to candidates" 80% of the sample answered yes. When they posed the question. "Should laws be passed to prohibit interest groups from contributing to campaigns, or do groups have a right to contribute to the candidate they support? only 40% said yes (Source A Mathematician Reads the Newspaper, by J. A Paulos. New York: Basic Books, 1995, p 15). Explain what this example illustrates, and use your answer to differentiate between sampling error and other types of vanability in survey results.