You are determining the sample size needed to estimate a percentage. Which method below would you NOT use to estimate the variance in the population?
a. Conduct a pilot study of 100 people.
b. A study on the same population that was conducted last year.
c. A study on the same population that was conducted two years ago.
d. Take the maximum variance of 50/50.
e. Estimate the range and divide by 6.
Answer: e. Estimate the range and divide by 6.