In an experimental digital control system, logic 0 is represented by -1 Volt and logic 1 is represented by +1 Volt. The voltage level is governed by a discrete r.v. Kwith PDF with any p (i.e. probability) k = +1 fr (k) = {1- p k = -1 elsewhere a) Draw the pdf b) Find E{K}, E{K?} and variance of Kin terms of p. c) Find the p value where the variance is maximized.