In a (Fictitious) Group Project, Two Interviewers Shared the Data

Essay

In a (fictitious) group project, two interviewers shared the data collection for one sample. Each stood by the campus bookstore entrance and asked people who went into the bookstore whether they thought the bookstore's prices were too high.
Interviewer #1's results: 33 said "yes"; 27 said "no"
Interviewer #2's results: 15 said "yes"; 25 said "no"
A) Name the type of sample the interviewers used and discuss it in terms of bias.
B) Combing the data in their samples together, give a confidence interval that has a "pretty good" confidence level for the population parameter.
(Note: Part B uses 32.2.)