The elements of the set {x : x ∈ Z and x² ≤ 9} are :

1. 3 and -3

2. {-3, -2, -1, 0, 1, 2, 3}

3. -2, -1, 0, 1 and 2

4. -3, -2, -1, 0, 1, 2 and 3

If A and B are two equal sets, then A - B is equal to :

1. A

2. B

3. {0}

4. { }

A set has 5 elements, then number of its subsets is :

1. 2⁵

2. 5²

3. 2⁵ - 1

4. 2 x 5

Let M = {factors of 12} and N = {factors of 24} then {24} is equal to :

1. M ∪ N

2. M ∩ N

3. M - N

4. N - M