Washington University banned smoking on the Hilltop campus starting in 2010. The student paper decides to do an opinion poll to see if current campus students/faculty/staff support the ban. Reporters are about to start asking a sample of 250 Hilltop people for their opinions.
(a) Describe a method of gathering opinions that would result in a poll bias in favor of the ban.
(b) Describe a method of gathering opinions that would result in a poll bias against the ban.
(c) Describe a method of gathering opinions that would keep the amount of bias in the poll results to a minimum