’NET Go to www.researchinfo.com. Click on “Marketing Research Calculators.” Which of the calculators can be used to help find the sample size required? How big of a sample is needed to make an inference about the U.S. population ±5 percent? How large a sample is needed to make an inference about the population of Norway ±5 percent? Remember, population statistics can be found in the CIA World Factbook online. Comment.