(a) You have been hired by Intel to determine the proportion of computer owners who plan to upgrade to a new operating system. Assuming that you want to be 95% confident that your sample proportion is within 0.02 of the true population proportion, how many people must you survey?

(b) Suppose that, in conducting the survey described in part a, you find that half of the people called refuse to answer the survey questions because they believe that you are trying to sell them something. If you proceed by calling twice as many people so that your sample size is large enough, will your results be good? Explain.