By elemental analysis of a biomass sample, it was found that the cells in the given sample are composed of (by weight) $\mathrm{C}=50 \%, \mathrm{H}=8 \%, \mathrm{O}=20 \%, \mathrm{~N}=10 \%$ and ash content $=12 \%$. Which of the following is the correct empirical formula of the ashfree cells, normalized with respect to Nitrogen?
- $\mathrm{C}_{5.8} \mathrm{H}_{11.2} \mathrm{O}_{1.7} \mathrm{~N}$
- $\mathrm{C}_{5.0} \mathrm{H}_{10.2} \mathrm{O}_{1.1} \mathrm{~N}$
- $\mathrm{C}_{6.8} \mathrm{H}_{12.2} \mathrm{O}_{2.1} \mathrm{~N}$
- $\mathrm{C}_{4.8} \mathrm{H}_{9.2} \mathrm{O}_{3.1} \mathrm{~N}$
