In an America OnLine poll of 671 people, 36% answered yes when asked if today's NFL games are too long.

a. What is the number of respondents who answered yes?

b. Among the respondents, 40 answered by saying that they were not sure. What is the percentage of "not sure" responses?

c. Given that the possible responses are "yes, no, not sure," what is the level of measurement of those responses? (nominal, ordinal, interval, ratio)

d. Given that the poll was conducted by asking America OnLine users to respond to a question that was posted on the Web site, what do you conclude about the poll results? Is it likely that the results reflect the opinion of the general population?