Explain why it is important to calculate a confidence interval.

Explain the meaning of the term "95% confidence

For a fixed level of confidence, what happens to a confidence interval forwhen we increase the sample size?

Suppose that for a sample size of n=100, we find that the sample mean is 50. Assuming that the standard deviation = 2, calculate the confidence intervals for the population meanwith the following confidence levels.

a.90%

b.92%

c.95%

d.97%

e.99%

Explain how the standard deviation of the t curve changes as the number of degrees of freedom describing a t curve increases.