1. Teenage Entertainment A random sample of 49 teenagers was surveyed, and the average number of movies that they had rented in the past week was 1.9, with a sample standard deviation of 0.5. Construct a 95% confidence interval for the average number of movies rented by teenagers in a week. (Round answers to 2 decimal places.)

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(b) Your regional manager at Sonic Video responds with the following memo:

TO: G.E.Cost
FROM: V. Meluzio
SUBJECT: Your job status
GC: Once again, you have failed to provide the accurate information we need (where was it that you got that A in a quantitative methods?) I thought you had hit rock bottom after the "Mars Attacks" debacle, but it now appears that you have started to dig. Indeed, you might recall, in the very dim recesses of your mind, that I specifically requested an error range of no more than plus/minus 0.1 in your estimate of the number of movies per teenager per week, and you came up with an error almost 50% too high. Kindly submit a confidence interval with a spread of no more than plus/minus 0.1 with a 95% confidence level by tomorrow at 9 am. or you are fired.

How large a sample should you now poll in order to save your job?

2. Spicy Pickles The Zesty Pickle Company advertises that its pickles have a mean spiciness of 7.5, and you are an avid pickle eater. You suspect that either your taste buds are degenerating, or the spiciness of Zesty pickles has been declining lately, so you hire a consumer agency to test the spiciness of Zesty pickles. It tests a total of 16 randomly selected pickes (its budget has been slashed by Congress) and finds a mean spiciness of 7.3 with a sample standard deviation of 0.3. Give a 95% confidence interval for the spiciness of Zesty pickles based on the results of the consumer agancy. Based on the confidence interval, is the company's advertising advertising accurate?