The basic functional unit of the human kidney is

The richest sources of vitamin $B_{12}$ are

If the rate of disappearance of $N_2O_5$ in the following reaction is $1.2 \times 10^{-5} \ mol \ L^{-1} \ s^{-1}$,the rate of production of $NO_2$ in $mol \ L^{-1} \ s^{-1}$ is:
$2 \ N_2O_{5(g)} \longrightarrow 4 \ NO_{2(g)} + O_{2(g)}$

If the straight line $2x + 3y + 1 = 0$ bisects the angle between a pair of lines,one of which is $3x + 2y + 4 = 0$,then the equation of the other line in that pair is:

${ }^{15}P_8 = A + 8 \cdot { }^{14}P_7 \Rightarrow A = $

Dividing the interval $[0,6]$ into $6$ equal parts and by using the trapezoidal rule,the value of $\int_0^6 x^3 dx$ is approximately: