An unbiased die is tossed $500$ times. The standard deviation of getting sixes in these $500$ tosses is

If a fair coin is tossed $8$ times, then the probability of getting at most $2$ heads is...

$A$ variable $X$ takes values $0, 0, 2, 6, 12, 20, ..., n(n-1)$ with frequencies $^nC_0, ^nC_1, ^nC_2, ^nC_3, ^nC_4, ^nC_5, ..., ^nC_n$, respectively. If the mean of this data is $60$, then its median is:

If $12$ dice are thrown at a time,then the probability that a multiple of $3$ does not appear on any dice is

Two cards are drawn at random one after the other with replacement from a pack of playing cards. If $X$ is the random variable denoting the number of ace cards drawn, then the mean of the probability distribution of $X$ is

$A$ fair coin is tossed $n$ times such that the probability of getting at least one head is at least $0.9$. Then the minimum value of $n$ is: