1. (45%) A random sample of 58 college students shows that average weight is 139 lbs with a Standard deviation of 20 lb.
2. Construct a 90 percent confidence interval for the mean weight of all college students.
3. Does the result in part (a) means that 90% of students' weight is in the range of your CI?
4. If you want to be 99% confident instead, and you want to control the maximal error of estimation to be 2 lbs, how many more college students need to be collected?

1. (55%) A random sample of 64 Male college students shows that average weight is 166 lb. with a Standard deviation of 25 lb.
2. At 5% level of significance, does the sample provide enough evidence to prove that the mean weight of all college students is more than 163 lb.?
3. Also explain the meaning of alpha and P-value occurred in the content of this problem.
4. Describe what kind of error it is for type II error in the content of this problem.