Which form more when you pour it, Coke or Pepsi ? Here are measurements by Diane War field on the form of volume (mL) after pouring a 12-oz can of coke, based on a sample of 12 cans:

And here are measurements for Pepsi, based on a sample of 12 cans:

a. Verify graphically that normality is an appropriate assumption.

b. Calculate a 99% confidence interval for the population difference in mean volumes.

c. Does the upper limit of your interval in (b) give a 99% lower confidence bound for the difference between the two micros? If not, calculate such a bound and interpret it in terms of the relationship between the foam volumes of Coke and Pepsi.

d. Summarize in a sentence what you have learned about the foam volumes of Coke and Pepsi.

312.2 292.6 331.7 355.1 362.9 331.7 292.6 245.8 280.9 320.0 273.1 288.7 148.3 210.7 152.2 117.1 89.7 140.5 128.8 167.8 156.1 136.6 124.9 136.6