Answer:
128 posibilities
Step-by-step explanation:
We have 7 colleges (A,B,C,...,H) which form a set with seven elements.
What you are asking is the number of elements (or cardinality) of the set that contains all possible sets formed by those 7 elements (or the "power set").
It is known that if n is the number of elements of a given set X, then the cardinality of the power set is [tex]2^n[/tex].
Therefore, there are [tex]2^7[/tex] or 128 possibilities (or elements) for the set of colleges that he applies to.