A digital communication system transmits one of the three values -1,0,1. A channel adds noise to cause the decoder to sometimes make an error. The error rates are 12.5% if a -1 is transmitted, 75% if a 0 is transmitted, and 12.5% if a 1 is transmitted. If the probabilities for the various symbols being transmitted are P [ - l ] = P[l] = 1/4 and P[0] = 1/2, find the probability of error. Repeat the problem if P[-1] = P[0] = P[l]