Using the provided information in the following paper chromatogram: The calculated R f value of A   is…

${\mathrm{R}}_{\mathrm{f}} =\frac{ \mathrm{Distance} \mathrm{travelled} \mathrm{by} \mathrm{compound} }{ \mathrm{Distance} \mathrm{travelled} \mathrm{by} \mathrm{solvent} }$

On chromatogram distance travelled by compound is $\to 2 \mathrm{cm}$

Distance travelled by solvent$=5 \mathrm{cm}$

So, ${\mathrm{R}}_{\mathrm{f}}=\frac{2}{5}=4\times {10}^{-1}=0.4$