1.What could be the possible ‘one’s’ digits of the square root of each of the following numbers?
(i) 9801

(ii) 99856

(iii) 998001

(iv) 657666025

One’s digit of any number depends on the one’s digit of the number of which it is square of. Here we have:
(i) One’s digit in the square root of 9801 can be 1 or 9.

(ii) One’s digit in the square root of 99856 can be 4 or 6.

(iii) One’s digit in the square root of 998001 can be 1 or 9.

(iv) One’s digit in the square root of 657666025 can be 5.