The reagent used for the conversion of allyl alcohol to propenal is

$A$ transverse sinusoidal wave moves along a string in the positive $x-$ direction at a speed of $10\, cm/s$. The wavelength of the wave is $0.5\, m$ and its amplitude is $10\, cm$. At a particular time $t$,the snapshot of the wave is shown in the figure. The velocity of point $P$ when its displacement is $5\, cm$ is:

$A$ Zener diode,having a breakdown voltage equal to $15 \, V$,is used in a voltage regulator circuit as shown in the figure. The current through the diode is ..... $mA$.

The oxidation number of $C$ in $HNC$ is .......

The number of four-letter words that can be formed using the letters of the word $BARRACK$ is:

What is the slope of the straight line for the graph drawn between $\ln k$ and $\frac{1}{T}$,where $k$ is the rate constant of a reaction at temperature $T$?