NYU Dual Degree

Is it possible to earn a dual degree across two schools at NYU, and if so how should I indicate that I would like to do so on the Common Application?
Also (not specifically NYU, but for college in general), when you apply through the Common App, are you accepted into the entire college or just the school that you selected? If you were to change your major once you started college and want to attend a different school within the college, would you be able to switch or would you have to choose a new major within the school you were originally accepted into?