Write the squares of all natural number from 30 to 99.

Q. Write 168 as difference of the square of two natural numbers.

Q. Write natural numbers from $30$ to $45$. What fraction of these numbers is odd?

Q. Write all the natural numbers from 2 to 12. fraction of them are prime numbers.

Q. Find the mode of the digits used in writing the natural numbers from 11 to 30.