The word deviate is not particularly unusual. Why does any word mean anything? Usage becomes established, and that's what people mean when they use that word.The prefix "de" means "from."
Most probably not. But it should be close to the population mean if various conditions are met:For example, the population should consist of independent, [nearly] identically distributed variables,...
The mean distance is the same as the mean of a set of numbers,but this time, instead of them just being numbers, they're lengths. You just simply add up all the numbers and divide the total length,...