Premeditated murder in Norway

My 15 year old cousin was strangled to death by her neighbor. He pled guilty and they are now discussing the penalty. The possibilities? He may get somewhere from 10-16 years in prison, at least that is what they are discussing right now. The max would have been 21, but since he pled guilty they are reducing it some, and because of his young age (18), he may get another reduction. I am not sure what his age got to do with anything. He wasn’t 8; he knew what he was doing. Guess what I think of the Norwegian penal system? Guess what I think would be a suitable punishment. The answer is far from 10-16 years in a posh Norwegian prison, that’s for sure.