Why do we use the "t-distribution" in the Chapter 2?

A.Because the "t-distribution" is always more precise than the normal distribution.

B.We can choose arbitrarily the t-distribution or the normal distribution. Since in Chapter 1,

we use normal distribution. For here, we use t-distribution.

C. If we only have limited measurements, the normal distribution can't describe the

distribution accurately Hence, we develop the t -distribution to solve it.

D. T-distribution is easier to use than the

normal distribution.