If set P = {factors of 8}, then set P is equal to :

1. {2, 4, 8}

2. {1, 2, 4}

3. {1, 2, 4, 8}

4. none of these

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 n(A) = n(B) then :

1. A = B

2. A ≠ B

3. A - B = {0}

4. none of these

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

1. 2⁵

2. 5²

3. 2⁵ - 1

4. 2 x 5