State, whether the square of the following numbers is even or odd ?

(i) 23

(ii) 54

(iii) 76

(iv) 75

(i) 23

Digit at ones place = 3

Square of 3 is 9.

So, digit at ones place of square number = 9

Hence, square of 23 is odd.

(ii) 54

Digit at ones place = 4

Square of 4 is 16.

So, digit at ones place of square number = 6

Hence, square of 54 is even.

(iii) 76

Digit at ones place = 6

Square of 6 is 36.

So, digit at ones place of square number = 6

Hence, square of 76 is even.

(iv) 75

Digit at ones place = 5

Square of 5 is 25.

So, digit at ones place of square number = 5

Hence, square of 54 is odd.