How does admissions into CMU colleges work?

<p>Several questions!</p>

<p>So on the Common App it says that I have to rank my colleges. Does this mean that I will get a separate decision from each college? Like you've been accepted into CIT but waitlisted in MCS and rejected from this other college? Or are you accepted into Carnegie Mellon as a whole?</p>

<p>The essay itself on the supplement asks to justify the college choices. If I put multiple colleges, do I have to justify each one individually, or is it recommended that I just stick to applying to one college?</p>

<p>I'm currently planning on ranking CIT as my first choice, with SCS in second. I really like electrical but I'm about equally interested in CS. Knowing that CMU has one of the best CS programs, is it better to straight away apply to CS or could i switch to SCS from CIT. Is that an easy process or near impossible?</p>

<p>Thank you in advance! :)</p>