$DDT$ residues are rapidly passed through the food chain causing biomagnification because $DDT$ is:

The four arithmetic means between $3$ and $23$ are

The line $\frac{x}{a} + \frac{y}{b} = 1$ moves in such a way that $\frac{1}{a^2} + \frac{1}{b^2} = \frac{1}{2c^2}$,where $a, b, c \in R_0$ and $c$ is a constant. Then,the locus of the foot of the perpendicular from the origin on the given line is -

Which of the following is an incorrect statement?

$A$ mass $m$ is supported by a massless string wound around a uniform hollow cylinder of mass $m$ and radius $R$. If the string does not slip on the cylinder,with what acceleration will the mass fall on release?

The heat energy absorbed by a system undergoing the cyclic process shown in the figure is: