Sagot :
They are: ∅, {a}, {b}, {c}, {a, b}, {a, c}, and {b, c}. Note that {a, b, c} is not a proper subset of {a, b, c}. Also, note that there is always one less proper subset than there are subsets of a set since a set cannot be a proper subset of itself.
Answer:
A proper subset of a set A is a subset of A that is not equal to A
Explanation: