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.
Shake hands or use the telephone right after that sneezing secretary, then touch your eyes, and you've got it, babe. Depending on the specific germ, the incubation period is between 12 hours and 5 days, usually 48 hours. To answer your question, the common cold is contagious between 24 hours before onset of symptoms until 5 days after onset. Like everything else this varies depending on the organism, but that's a pretty safe estimate.