What chance do i have of getting into cornell? or brown?

i am a sopre in high school right now and my GPA is a 4.0 and i am in all AP cles. i am a member of the model UN club, the math club, chamber singers, and the jazz band. i participated in many science competitions and the math fair. i also did brain research in a lab with a mentor for the past two summers and i will be doing it again this summer. i participate in all the school plays and dramas. i also have sang in carnegie hall twice. i didnt take the SAT yet but i took the PSAT and i got a 68 out of 80 on the critical reading a 70 on the writing and a 75 on the math. i also did some comunity service and i am a member of the national honor society, the spanish honor society, and the science honor society.