1. Explain what is meant by the margin of error for a confidence interval. What error are we talking about in the context of an interval for m?
2. Explain exactly what we mean when we say that a sample of size n makes us 99 percent confident that x is within E units of m.
3. Why do we often need to take a preliminary sample when determining the size of the sample needed to make the margin of error of a confidence interval equal to E?