Given a likely range for the observed value of a sample proportion p. Based on the given range, identify the educated guess that should be used for the observed value of p to calculate the required sample size for a prescribed level and margin of error.
a. .4 to .7
b. .7 or greater
c. .7 or less
d. In each of part a-c, which observed values of the sample proportion will yield a larger margin of error than the one specified if the educated guess is used for the sample size computation?