sunflower

It depends.
Some schools like Carnegie, Duke require you to provide FS, but many other top schools don't do the same way.

So investigate the schools carefully...

sunflower

All the schools require, except you get full scholarship. As for the money, it depends. At least the tuition and expenses for the first school year.

sunflower

3 months are enough. But the longer and the more, the better.

sunflower

Best of luck to you!