$$0.400 \mathrm{~g}$$ of an organic compound $$(\mathrm{X})$$ gave $$0.376 \mathrm{~g}$$ of $$\mathrm{AgBr}$$ in Carius method for estimation of bromine. $$\%$$ of bromine in the compound $$(\mathrm{X})$$ is ___________.

(Given: Molar mass $$\mathrm{AgBr=188~g~mol^{-1}}$$

$$\mathrm{Br}=80 \mathrm{~g} \mathrm{~mol}^{-1}$$)

See the following chemical reaction:

$$\mathrm{Cr}_{2} \mathrm{O}_{7}^{2-}+\mathrm{XH}^{+}+6 \mathrm{~F}_{e}^{2+} \rightarrow \mathrm{YCr}^{3+}+6 \mathrm{~F}_{e}^{3+}+\mathrm{Z} \mathrm{H}_{2} \mathrm{O}$$

The sum of $$\mathrm{X}, \mathrm{Y}$$ and $$\mathrm{Z}$$ is ___________

$$1 \mathrm{~g}$$ of a carbonate $$\left(\mathrm{M}_{2} \mathrm{CO}_{3}\right)$$ on treatment with excess $$\mathrm{HCl}$$ produces $$0.01 \mathrm{~mol}$$ of $$\mathrm{CO}_{2}$$. The molar mass of $$\mathrm{M}_{2} \mathrm{CO}_{3}$$ is __________ $$\mathrm{g} ~\mathrm{mol}^{-1}$$. (Nearest integer)

The orbital angular momentum of an electron in $$3 \mathrm{~s}$$ orbital is $$\frac{x h}{2 \pi}$$. The value of $$x$$ is ____________ (nearest integer)