Can you Please resolve these Sub arguments???

[motsivad]

Me and my friend who both have an interest in subs, but are far less knowledgeable than some of the guys on here. Can you clear up one or two disagreements we have.

1) What is faster Nuclear propulsion, or modern day Diesel-Electric?

I always thought it was nuclear but he is certain that D-E is comparable. From my Knowledge the nuclear propulsed Alfa class is the fastest sub in the world and can easily exceed 40 knots and the LA class can do about 35+. From my knowledge D-E's tend to average mid 20s.

2) When submerged is Nuclear quieter or Modern day Electric?

I say former, he says latter

3) When surfaced is nuclear or Diesel quieter

I think it's gotta be nuclear, but he insists Diesel