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Ski wax Bjork Larsen was trying to decide whether to use a new racing wax for cross-country skis. He decided that the wax would be worth the price if he could average less than 55 seconds on a course he knew well, so he planned to study the wax by racing on the course 8 times. His 8 race times were \(56.3,65.9,50.5,52.4,46.5,57.8,52.2,\) and 43.2 seconds. Should he buy the wax? Explain by using a confidence interval

64\. Wind power Should you generate electricity with your own personal wind turbine? That depends on whether you have enough wind on your site. To produce enough energy, your site should have an annual average wind speed above 8 miles per hour, according to the Wind Energy Association. One candidate site was monitored for a year, with wind speeds recorded every 6 hours. A total of 1114 readings of wind speed averaged 8.019 mph with a standard deviation of 3.813 mph. You've been asked to make a statistical report to help the landowner decide whether to place a wind turbine at this site. a. Discuss the assumptions and conditions for constructing a confidence interval with these data. Here are some plots that may help you decide. b. Based on your confidence interval, what would you tell the landowner about whether this site is suitable for a small wind turbine? Explain.