For the right tail, is it appropriate to just calculate a mean and standard deviation, add 1, 2 & 3 standard deviations from the mean to create a range then compare that to the normal 68/95/99.7 for the standard normal distribution after using the norm.dist function in excel to test each standard deviation value.
The contagious period for a cold lasts about three to four days into the illness. As a general rule, people with a cold are most contagious about three days after their initial exposure to the virus. For more information on colds, influenza and related topics, check out the links on the next page.
During the two-week period when you're contagious, research indicates that you'll be most likely to transmit the cold virus when you're experiencing cold symptoms. The period when you're most contagious is when your symptoms are at their worst -- day 2 to day 4 of the cold.