$A$ body cools from $62^{\circ}C$ to $50^{\circ}C$ in $10$ minutes and to $42^{\circ}C$ in the next $10$ minutes. The temperature of the surrounding is ........... $^{\circ}C$.

If $\frac{x-4}{x^2-5x+6}$ can be expanded in the ascending powers of $x$,then the coefficient of $x^3$ is

Choose the correct option regarding the following complex compounds which follows $(F)$ and does not follow $(NF)$ the Sidgwick $EAN$ rule:
$(I) \ [(Ph_3P)_2PdCl_2]$
$(II) \ [NiBrCl(en)]$
$(III) \ Na_4[Fe(CN)_5NOS]$
$(IV) \ Cr(CO)_3(NO)_2$
$(I) - (II) - (III) - (IV)$

In which of the following does aluminum become passive?

If the angle between the lines joining the origin to the points of intersection of $x+2y+\lambda=0$ and $2x^2-2xy+3y^2+2x-y-1=0$ is $\frac{\pi}{2}$,then a value of $\lambda$ is

Which of the following have sunken stomata?