Find E(x), E(x2), the mean, the variance, and the standard deviation of the random variable whose probability density function is given below. 1 f (x) = 18 x, [0,6] . . . . . E(x) (Type an integer or a simplified fraction.) E(x2) = (Type an integer or a simplified fraction.)E(x2) =| |(Type an integer or a simplified fraction.) H = (Type an integer or a simplified fraction.) 62 = (Type an integer or a simplified fraction.) O= (Type an exact answer, using radicals as needed.)