Water is considered to be polluted if the dissolved oxygen $(D.O.)$ content is less than ... $ppm$ :

The minimum force required to move a body up an inclined plane is three times the minimum force required to prevent it from sliding down the plane. If the coefficient of friction between the body and the inclined plane is $\frac{1}{2 \sqrt{3}}$,then the angle of the inclined plane is (in $^{\circ}$)

Which of the following lacks a capsid?

$A$ closed compartment containing gas is moving with some acceleration in the horizontal direction. Neglect the effect of gravity. Then the pressure in the compartment is

The area (in sq units) bounded by the curves $y^2=4x$ and $x^2=4y$ is

The relation between $(A)$ and $(B)$ is: