Analysis of an adsorption data showed that the Langmuir isotherm constant $K^{-1}=\frac{k_a}{k_d},$ for the adsorption of $N_2$ on activated charcoal is $5\mathrm{.}561{10}^{-5}P{a}^{-1}.$ Calculate the pressure of $N_2$ at $15\%,35\%,55\%,75\%$ and $95\%$ coverage.