Pizza sales. A national food product company believes that it sells more frozen pizza during the winter months than during the summer months. Average weekly sales for a sample of stores in the Baltimore area over a one-year period provided the following data for sales volume (in pounds) during the two seasons. Assume that the two seasonal sales have different population standard deviations. Season N Mean StDev Minimum Maximum Winter 13 31234 13500 15312 73841 Summer 14 22475 8442 12743 54706 You want to investigate whether winter sales is the same with summer sales. Which among the following tests should you use? a. two sample z test
b. two sample pooled-t test (equal population standard deviation)
c. two sample t test with unequal population standard deviation
d. paired t test