Four alkali metals $A$,$B$,$C$ and $D$ have standard electrode potentials $-3.05 \ V$,$-1.66 \ V$,$-0.40 \ V$ and $0.80 \ V$ respectively. Which metal will be the most reactive?

If $f$ is an even function defined on the interval $(-5, 5)$,then four real values of $x$ satisfying the equation $f(x) = f\left( \frac{x + 1}{x + 2} \right)$ are

Which one of the following statements is $NOT$ the property of light?

$A$ black body at a temperature of $227^{\circ}C$ radiates heat energy at the rate of $5 \ cal/cm^2-sec$. At a temperature of $727^{\circ}C$,the rate of heat radiated per unit area in $cal/cm^2-sec$ will be:

The sum of the coefficients in the expansion of $(1+x+x^2)^n$ is

Consider the following reaction: $C_6H_5NO_2$ $\xrightarrow{Sn/HCl} X$ $\xrightarrow{C_6H_5COCl} Y + HCl$. What is $Y$?