The probability distribution of the number of doublets in four throws of a pair of dice is given by

Let $$\vec{v}=2 \hat{i}+2 \hat{j}-\hat{k}$$ and $$\bar{w}=\hat{i}+3 \hat{k}$$. If $$\bar{u}$$ is a unit vector, then the maximum value of the scalar triple product $$[\bar{u} \bar{v} \bar{w}]$$ is

S1 : If $$-$$7 is an integer, then $$\sqrt{-7}$$ is a complex number

$$\mathrm{S} 2$$ : $$-$$7 is not an integer or $$\sqrt{-7}$$ is a complex number

For the probability distribution given by following

Var(X) =