For a reaction $\mathrm{A}\to \mathrm{B},$ enthalpy of reaction is $-4.2 \mathrm{kJ} {\mathrm{mol}}^{-1}$ and enthalpy of activation is $9.6 \mathrm{kJ}{ \mathrm{mol}}^{-1}.$ The correct potential energy profile for the reaction is shown in the option.

The slope of Arrhenius Plot $\left(\mathrm{lnk}\text{ v/s }\frac{1}{ \mathrm{T}}\right)$ of first order reaction is $-5\times {10}^3 \mathrm{K}.$ The value of ${\mathrm{E}}_{\mathrm{a}}$ of the reaction is. Choose the correct option for your answer.

[Given $\mathrm{R}=8.314 \mathrm{J} {\mathrm{K}}^{-1} {\mathrm{mol}}^{-1}$]