15. A medical research team studied the number of head and neck injuries sustained by hockey players. Of the 319 players who wore a full-face shield, 195 sustained an injury. Of the 323 players who wore a half-face shield, 204 sustained an injury. At a = 0.10, can you reject the claim that the proportions of players sustaining head and neck injuries are the same for the two groups? Interpret the decision in the context of the original claim. (Source: The Journal of the American Medical Association) 16. A random sample of 40 ostrich eggs has a mean incubation period of 42 days. Assume the population standard deviation is 1.6 days. (a) Construct a 95% confidence interval for the population mean incubation period. (b) A zoologist claims that the mean incubation period for ostriches is al least 45 days. At a = 0.05, can you reject the zoologist's claim? Interpret the decision in the context of the original claim. 17. A researcher claims that 18% of dog owners dress their dogs in outfits, Describe type I and type II errors for a hypothesis test of the claim. (Source: Consumer Reports)