A social scientist wants to use subjects' number of hours of television watched to predict their score on a test of propensity to violence. Subjects who watch more television do tend to get higher scores on the test. But regressing their violence test score on their hours of television watch explained only 16% of the total score. What is the correlation between their hours of television watched and violence test scores?

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Tardigrades, or water bears, are a type of micro-animal famous for their resilience. In examining the effects of radiation on organisms, an expert claimed that the amount of gamma radiation needed to sterilize a colony of tardigrades no longer has a mean of 1150 Gy (grays). (For comparison, humans cannot withstand more than 10 Gy.) A random sample of 25 tardigrade colonies found that the amount of gamma radiation needed to sterilize a colony had a sample mean of 1133 Gy, with a sample standard deviation of 02 Gy. Assume that the population of amounts of gamma radiation needed to sterilize a colony of tardigrades is appraximately normally distributed. Complete the parts below to perform a hypothesis test to see if there is enough evidence, at the 0.05 level af significance, to support that H, the mean amount of gamma radiation needed to sterilize a colony of tardigrades, is not equal to 1150 Cy. (a) State the null hypothesis H, and the alternative hypothesis H, that you would use for…