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

The oxoacid of sulphur which contains two sulphur atoms in different oxidation states is

If the roots of the quadratic equation $x^2 + px + q = 0$ are $\tan 30^\circ$ and $\tan 15^\circ$ respectively,then what is the value of $2 + q - p$?

$A$ particle is moved from $(0, 0)$ to $(a, a)$ under a force $\vec F = (3\hat i + 4\hat j)$ along two paths. Path $1$ is $OP$ and path $2$ is $OQP$. Let $W_1$ and $W_2$ be the work done by this force in these two paths respectively. Then

Oxidation states of $P$ in $H_4P_2O_5, H_4P_2O_6, H_4P_2O_7$ are respectively:

Two numbers are chosen at random from $\{1, 2, 3, 4, 5, 6, 7, 8\}$ at a time. The probability that the smaller of the two numbers is less than $4$ is