2 Questions about Rape..?

Okay so my stepfather thinks he is smarter than me and I basically know nothing.... About anything... So here is my questions..

Can a man be raped?

Doesn't most rapees know their rapist?

Men can become erect through other things.. Not just being turned on. Friction, fear, pain, no reason at all, just random things can turn a man on. When you are sleeping and you are entering REM you may become erect. When you wake up with "Morning" wood. That is because you were completely relaxed.. He says there is no other way besides being turned on your penis can become erect -_-.... He says I do not know what I am talking about ...

About women knowning their attacker... 70-80 percent of women know their attacker... He says thats not true.. He said mostly women are walking down the street and get raped.. He says the woman most likely gets punched so she is knocked out, raped, and left there. He annoys me so much... He said that I do not know what I am saying, what I am talking about, I just think I do because I must have seen something about it once or twice... He is getting to the point where he basically acts like I know NOTHING... Like its a magic that I am able to walk around without drooling on myself..

Am I right? Is he right? ( please lets not go into child sex though, like age 0-17 because thats in a different ballpark that me and him are talking about. I understand they cannot consent but I am mostly talking about 18+ rape.)

If you could also post where you got your evidence to back up your answer that would be nice. If you do not have a website to back you up, thats okay I just want to be able to be like... "Look here" lol thanks for your time.