10. (a). Suppose the Taylor expansion of the moment generating function of a random variable is m(t) = 1 + 3t + 6t + ... Find the mean and variance of this random variable. (b). Please examine the Taylor expansion of the following three functions and tell which ones cannot be moment generating functions: m(t) = 0.1+t+21 + m(t) = 13t+ 4t + m3(t) = 1 + 2t + 3t + ... ...