For ? = 25 independent observations from a normal population whose true mean μ and true standard deviation σ are both unknown: 1. How many degrees of freedom does the relevant Student's t distribution...

For ? = 25 independent observations from a normal population whose true

mean μ and true standard deviation σ are both unknown:
1. How many degrees of freedom does the relevant Student's t distribution

have?
2. Construct a level C=95% confidence interval for the unknown mean μ
3. Compute (as numbers) the endpoints of the confidence interval if the

sample mean is ?̅
25 = 3.65 and the sample standard deviation is ?25 = 0.82