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4. The average greyhound can reach a top speed of 19.2 meters per second. A particular greyhound breeder claims her dogs are faster than the average greyhound. A sample of 30 of her dogs ran, on average, 19.5 meters per second with a population standard deviation of 0.9 meters per second. With 0: = 0.10, is her claim correct? A) Yes, because the test value 2.51 > 1.65. B) No, because the test value 2.51 1.28 D) Yes, because the test value 1.83 > 1.28 5. At a certain university, the average attendance at basketball games has been 4018. This year the attendance for the rst 12 games has been 4315 with a standard deviation of 350. The athletic director claims that the attendance is the same as last year. If a: .01 , what are the critical values for this two-tailed t test? A) $1.261 B) $2.021 C) i3.106 D) $1.796 6. Reginald Brown, an inspector from the Department of Weights and Measures, weighed 20 sixteen-ounce cereal boxes of corn akes. He found their mean weight to be 15.8 ounces with a standard deviation of 0.3 ounces. At a = 0.05, are the cereal boxes lighter than they should be? A) Yes, the cereal boxes are lighter than they should be. B) No, the cereal boxes are not lighter than they should be. C) The cereal boxes are heavier than they should be. D) The cereal boxes are about the same weight which they should be