In comparing means for two independent samples, suppose that μ1 = μ2 = 0, σ1 = σ2 = 3, and n1 = n2 = 30.
a. Draw a picture of the appropriate sampling distribution, and show where the value x‾1 - x‾2 = 2 falls on it.
b. Find the value of the standardized statistic corresponding to x‾1 - x‾2 = 2.
c. Draw a picture of the standard normal distribution with the standardized statistic you found in part (b) shown on it. Compare it to your picture in part (a).