When $a^2$ is divided by $6$,which of the following cannot be the remainder? $(a \in N)$

If the Least Common Multiple $(LCM)$ of two numbers is equal to their product,then their Greatest Common Divisor $(GCD)$ is ........ .

If $\alpha, \beta$,and $\gamma$ are the zeros of the cubic polynomial $p(x) = ax^3 + bx^2 + cx + d$ where $a \neq 0$,then the product of its zeros $(\alpha \beta \gamma)$ is:

Express the number $3825$ as a product of its prime factors.

There is a circular path around a sports field. Sonia takes $18$ minutes to drive one round of the field,while Ravi takes $12$ minutes for the same. Suppose they both start at the same point and at the same time,and go in the same direction. After how many minutes will they meet again at the starting point?

$\pi$ is a . . . . . . type of number. (Rational,Irrational,Whole number)