Math help please?? 10 easy points!?

[Jobey]

For the first one:

(a) and (b) both have a selection bias in that you're asking people who are riding the buses (so they would probably all support better bus service). In addition, (a) has people self-selecting; only people with strong opinions are likely to respond. Further, in (a) they mention a website, so only young, technologically-savvy people with a home internet connection will work.

The phone book thing has much less bias, but these days it might count against young people with cell phones only. Further, many people won't have much familiarity with the bus service.

That's the first one. If you want the other ones, you need to describe your attempt.

Finally, the plural of question is questions, not question's (my pet peeve, it's just a plural).