Which of the following alkaline earth metal nitrides is volatile?

What is the pressure on a swimmer $20 \, m$ below the surface of water in $atm$?

Which of the following is not true for a eukaryotic cell?

If the lengths of the tangents drawn from a point $P$ to the three circles $x^2+y^2-4=0$,$x^2+y^2-2x+3y=0$,and $x^2+y^2+7y-18=0$ are equal,then the coordinates of $P$ are

If the point $P(1,3)$ undergoes the following transformations successively:
$(i)$ Reflection with respect to the line $y=x$.
(ii) Translation through $3$ units along the positive direction of the $X$-axis.
(iii) Rotation through an angle of $\frac{\pi}{6}$ about the origin in the clockwise direction.
Then,the final position of the point $P$ is

Which one of the following reactions occurs at the anode in the Castner process of extracting sodium metal?