I am sorry all.

May I ask the below questions?

(1)Suppose two random variables X and Y are positively correlated, If X is above its mean, then Y is also above its mean'?

(2)If two events A and B are not correlated, then P(B)P(A) = P(A and B)

(3)Suppose X is a binomial random variable, with a mean 10, standard deviation 5. Then 10000X is approximately a normalrandom variable.

Thanks a lot !!