(i) {x : x ∈ ℕ and (x - 1) (x - 2) = 0}

x can take the values 1 or 2 in the given case. The set is {,}. Hence, it is .

(ii) {x : x ∈ ℕ and x² = 4}

x² = 4, implies that x = + or -. But x ∈ ℕ or x is a number so the set is{}. Hence, it is .

(iii) {x : x ∈ ℕ and 2x - 2 = 0}

In a given set x = and 1 ∈ ℕ . Hence, it is .

(iv) {x : x ∈ ℕ and x is prime}

The given set is the set of all numbers. There are infinitely many numbers. Hence, set is

(v) {x : x ∈ ℕ and x is odd}

Since there are infinite number of numbers, hence the set is