In the Following Passage, Identifying Sample, Population, Attribute of Interest

In the following passage, identifying sample, population, attribute of interest, and the extent to which the claims involved are knowable. Consider carefully the size and diversification of the sample and the extent to which the population differs or may differ from the sample; remember, what's important is that the sample be representative. Would our professor's conclusion, "Sixteen percent of faculty nationwide deduct home office expenses on their federal income tax return," be more accurate if she restricted it to faculty in her own state?
A college professor converted one room of her house into a home office and intended to deduct her expenses on her federal income tax return. She wondered how many other college faculty had done the same, thinking that the more who deducted home offices, the less likely her own return would be noticed by the IRS and hence the less likely she would be audited. So she decided to do her own informal survey of her colleagues to see how many of them had home offices. She sent out a questionnaire of three questions to all 1,200 instructors at her campus, and she received 950 responses. (Her promise to share the results of the survey apparently motivated faculty to respond.)
As it turned out, 32 percent of her respondents answered yes to the question, "Do you maintain an office at home?" Half of these also answered yes to the question, "Do you deduct your home office expenses on your federal income tax return?" And 24 percent of the entire group of respondents answered yes to the question, "Is your campus office adequate?"