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1. (45%) A random sample of 50 college students shows that average weight is 138 Ibs with a Standard deviation of 25 lb. (a) Construct a 95 percent confidence interval for the mean weight of all college students. (b) Does the result in part (a) means that 95% of students' weight is in the range of your CI? (c) If you want to be 99% confident instead, and you want to control the maximal error of estimation to be 3 Ibs, how many more college students need to be collected