The equation $x^2-3 x y+\lambda y^2+3 x-5 y+2=0$, where $\lambda$ is real number represents pair of lines If $\theta$ is acute angle between the lines, then $\frac{\operatorname{cosec}^2 \theta}{\sqrt{10}}=$

If $\theta$ is the angle between the lines whose direction cosines are given by $6 \mathrm{mn}-2 \mathrm{n} l+5 l \mathrm{~m}=0$ and $3 l+\mathrm{m}+5 \mathrm{n}=0$, then $\sin \theta=$

If $X \sim B\left(6, \frac{1}{2}\right)$, then $P(|X-2| \leqslant 1)=$