NVIDIA interview questions

I applied through my university's coop system and got 2 phone interviews for 2 different teams. In the first interview the interviewer showed up 45 minutes late, and tried to cram the entire hour-long interview into 20 minutes. He sounded completely disinterested right from the start, and kept complaining about the sound quality. The second interview went a lot better, but the interviewer asked a lot of bad, vague, or just generally unanswerable questions.

It's a campus interview at our university's engineering and computer science career fair. You are given four questions and two of them are related to hardware and operation system. The other two are code design using C++. However, you only need to answer one of them. The second one is for bonus. Not difficult in general.