Plotting of graph
Identification of line representing lower mass
Reason
As $\mathit{\lambda }=\frac{\mathit{h}}{\sqrt{2\mathit{m}\mathit{e}\mathit{V}}}$
As the charge of two particles is same, therefore
$\frac{\mathit{\lambda }}{\left(\frac{1}{\sqrt{\mathit{V}}}\right)}\mathit{\alpha }\frac{1}{\sqrt{\mathit{m}}}$ i.e. slope $\mathit{\alpha }\frac{1}{\sqrt{\mathit{m}}}$
Hence, particle with lower mass $\left({\mathit{m}}_2\right)$ will have greater slope.