Given below are two statements about X-ray spectra of elements :

Statement (I) : A plot of $\sqrt{v}$ ( $v=$ frequency of X-rays emitted) vs atomic mass is a straight line.

Statement (II) : A plot of $v(\nu=$ frequency of $X$-rays emitted) vs atomic number is a straight line. In the light of the above statements, choose the correct answer from the options given below :

Consider the following reactions

$$\mathrm{K}_2 \mathrm{Cr}_2 \mathrm{O}_7 \xrightarrow[-\mathrm{H}_2 \mathrm{O}]{\mathrm{KOH}}[\mathrm{~A}] \xrightarrow[-\mathrm{H}_2 \mathrm{O}]{\mathrm{H}_2 \mathrm{SO}_4}[\mathrm{~B}]+\mathrm{K}_2 \mathrm{SO}_4$$

The products $[A]$ and $[B]$, respectively are :

Given below are two statements:

Consider the following reaction

Statement (I): In the case of formaldehyde is about 2280, due to small substituents, hydration is faster.

Statement (II) : In the case of trichloro acetaldehyde is about 2000 due to $-$I effect of $-$Cl .

In the light of the above statements, choose the correct answer from the options given below :

0.01 mole of an organic compound $(X)$ containing $10 \%$ hydrogen, on complete combustion produced $0.9 \mathrm{~g} \mathrm{H}_2 \mathrm{O}$. Molar mass of $(\mathrm{X})$ is _________ $\mathrm{g} \mathrm{~mol}^{-1}$.