$A$ die is thrown $100$ times. The standard deviation of getting an even number is:

If $X \sim B(4, p)$ and $2 P(X=3)=3 P(X=2)$,then the value of $p$ is:

If two coins are tossed $5$ times,then the probability of getting $5$ heads and $5$ tails is

$A$ fair coin is tossed a fixed number of times. If the probability of getting $7$ heads is equal to that of getting $9$ heads,then the probability of getting $3$ heads is

If $X \sim B(n, p)$ then $\frac{P(X=k)}{P(X=k-1)}=$

In a multiple-choice test consisting of $8$ questions,each question has four options. For each of the questions,exactly one of the four options is the right answer. $A$ student answers all the questions by choosing one option for each question. The number of ways in which the student can get exactly $5$ correct answers is