Paleomagnetic studies of Canadian volcanic rock known as the Carmacks Group have recently been completed. The studies revealed that the northward displacement of the rock units has an approximately normal distribution with standard deviation of 500 kilometers. One group of researchers estimated the mean displacement at 1500 kilometers, whereas a second group estimated the mean at 1200 kilometers. (Show your work with the formula you used)
a. Assuming the mean is 1500 kilometers, what is the probability of a northward displacement of less than 500 kilometers?
b. Assuming the mean is 1200 kilometers, what is the probability of a northward displacement of less than 500 kilometers?
c. If, in fact, the northward displacement is less than 500 kilometers, which is the more plausible mean, 1200 or 1500 kilometers?