PROBLEM 2 (8 PTS). Suppose that an equally likely binary message X, either -2 or +2, is to be transmitted from location A to location B via a channel, and the message sent is subject to a normal channel noise W ~ /(1, 2). The received signal Y at location B is given by Y = X + W. and the receiver decodes the message according to the following rule: . if Y 2 1, then decode the message as +2; . if Y