small triangle a)     The data obtained from a given experiment is a pair of numbers a and b, where a ³ 0 and b ³ 0. It is known that a and b have mean 1; what is the largest value that the standard deviation can be?

(b)     The data obtained from a given experiment is a triple of numbers x, y and z, where each is non-negative. It is known that the mean of x, y and z is 1; what is the largest value that the standard deviation can be?

(c)     The data obtained from a given experiment is a set of numbers t1,¼,tn, where each is non-negative. It is known that the mean of the tj is 1. Show that the standard deviation may be as large as
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