Let $A=\left[a_{i j}\right]$ be a square matrix of order $2$ with entries either $0$ or $1$ . Let $E$ be the event that $A$ is an invertible matrix. Then the probability $P ( E )$ is:

If the probability that a randomly chosen $6$-digit number formed by using digits $1$ and $8$ only is a multiple of $21$ is $p$, then $96\;p$ is equal to

A dice marked with digit $\{1, 2, 2, 3, 3, 3\} ,$ thrown three times, then the probability of getting sum of number on face of dice is six, is equal to :-

In a certain lottery $10,000$ tickets are sold and ten equal prizes are awarded. What is the probability of not getting a prize if you buy two ticket.

If a leap year is selected at random, what is the change that it will contain $53$ Tuesdays ?

The letter of the word `$ASSASSIN$' are written down at random in a row. The probability that no two $S$ occur together is