Hi! I'm Kristine. What is my vocal range? my lowest is G3 and my highest is B5. And what is falsetto? Thank you.
Your range is what you have said. As to whether that makes you a soprano or mezzo soprano - that's hard to tell without hearing you, knowing your age, etc. Your vocal fach is not only determinate by your range, but also by the tessitura your are comfortable with and also where the voice blossoms… where the voice sounds the best. Some mezzos have high Bs or Cs but they can't handle the tessitura of the soprano.
And some sopranos have good low notes but their voice shines most at the top of the range. I hope this helps.
As to falsetto - here is a site with a good definition: http://en.wikipedia.org/wiki/Falsetto
Best of luck to you!