sets: definition and operations

What is the empty set?
1. A set with only one element
2. A set with no elements
3. The empty set doesn’t exist
4. None of the above is correct
Which brackets are used to list the elements of a set?
1. Braces
2. Round brackets
3. Square brackets
4. None of the above is correct
Membership in a set is indicated by the symbol:
1. ∪
2. ∅
3. ∩
4. ∈
What is the intersection of two sets A and B?
1. It’s the set of all objects that are members of A, or B, or both
2. It’s the set of all objects that are members of both A and B
3. It’s the set whose members are all possible ordered pairs (a, b) where a is a mem
  ber of A and b is a member of B
4. It’s the set whose members are all possible subsets of A