USA Today reported on an Adecco Staffng survey of 1000 randomly selected adults. Among those respondents, 20% chose health benefits as being most important to their job.

a. What is the number of respondents who chose health benefits as being most important to their job?
b. Construct a 95% interval estimate of the proportion of all adults who choose health benefits as being most important to their job.
c. Based on the result from part (b), can we safely conclude that the true proportion is different from 1/4? Why?