On top of the vegetables list are cucumber and lettuce, consisting of 96 percent water. Zucchini, radish and celery are comprised of 95 percent water. Ninety-four percent of tomato's weight is water, and green cabbage is 93 percent water.
I looked at the process sigma calculator (button in upper right below the search box) and they present a link to a forum post (http://www.isixsigma.com/forum/showmessage.asp?messageID=437) that gives information on calculating the sigma using a normsinv function.
The Greek letter sigma is the commonly used mathematical symbol for population standard deviation. The Greek letter mu is also commonly used in calculations of the population standard deviation for non-overlapping populations. Continue Reading.