I am from India and am a 3rd year undergraduate student of B.Tech Engineering Physics at one of the best universities my country has to offer. This summer I am going to work under a professor on a research project in medical physics/biophysics - the area of my choice, at one of the top universities.
I have two more years left for my college and I can not think of a career other than physics. And thus, in this time I have decided to be single-minded for GRE preparation. Everything about this test is still unknown to me.
I would request the kind moderators and members to kindly clarify few of my basic doubts. I'd never forget your favor.
1. For applying to an MS degree at top research institutions at, say, US; what all tests under GRE do I have to take? All three - verbal, quantitative and subjective?
2. What do you suggest is the best way to prepare for the verbal and quantitative tests?
3. In your view, what would be a reasonable score to study my Master's in Physics in say, the top 30 research institutions in the US?
4. For candidates who marry after their graduation, do the universities in the US have a provision to accommodate such master's candidates?
5. What is the weight-age of a good GPA versus the research work you have involved yourself in during your 4 years as an undergraduate?
6. For physics, what would be the top universities in the states?
I'd be grateful to receive a kind and prompt reply.

Thank you so much!