Two dice are thrown simultaneously,the probability of obtaining a total score of $5$ is

Which of the following ethers cannot be produced by Williamson ether synthesis?

An inclined plane makes an angle of $30^{\circ}$ with the horizontal. $A$ solid sphere rolling down this inclined plane from rest without slipping has a linear acceleration equal to:

If the $x$-coordinate of a point $P$ on the line joining the points $Q(2, 2, 1)$ and $R(5, 1, -2)$ is $4$,then the $z$-coordinate of $P$ is

For $x \in \mathbb{R}$,the least value of $\frac{x^2-6x+5}{x^2+2x+1}$ is

Which of the following reagents would you use to separate $SO_4^{2-}$ ions from a solution containing a mixture of $SO_4^{2-}$ and $Cl^-$ ions?