Photochemical smog pollution does not contain

What is the final product $(B)$ of this sequence?

When two related populations occupy geographically or spatially separate areas,they are called

In a system of two particles of masses $m_{1}$ and $m_{2}$,the second particle is moved by a distance $d$ towards the centre of mass. To keep the centre of mass unchanged,the first particle will have to be moved by a distance:

The potential difference between the plates of a parallel plate capacitor is changing at the rate of $10^6\, V/s$. If the capacitance is $2\,\mu F$,the displacement current in the dielectric of the capacitor will be.....$A$

$A$ pair of perpendicular lines passes through the origin and also through the points of intersection of the curve $x^2+y^2=4$ with $x+y=a$,where $a>0$. Then $a$ is equal to