You are an operations analyst for AT&T. The length of long distance telephone calls may be normally distributed but you are not certain. You select a random sample of 25 calls. The average length is 8...

You are an operations analyst for AT&T. The length of long distance telephone calls may be normally distributed but you are not certain. You select a random sample of 25 calls. The average length is 8 min and the SD is 2 min. What % of these calls should be between 4.8 and 11.2 min?