Q25, chapter 5, intoduction to probability, Blitzstein. Please solve this question:

Alice is trying to transmit to Bob the answer to a yes-no question, using a noisy channel. She encodes yes as 1 and no as 0, and sends the appropriate value. However, the channel adds noise; specifically, Bob receives what Alice sends plus a N(0, ²) noise term (the noise is independent of what Alice sends). If Bob receives a value greater than 1/2 he interprets it as yes; otherwise, he interprets it as no. (a) Find the probability that Bob understands Alice correctly. (b) What happens to the result from (a) if is very small? What about if is very large? Explain intuitively why the results in these extreme cases make sense.