JEE Advanced 2018 Chemistry question

Consider the following reversible reaction,

A(g)+B(g)\rightleftharpoons AB(g).

The activation energy of the backward reaction exceeds that of the forward reaction by (in J mol). If the pre-exponential factor of the forward reaction is 4 times that of the reverse reaction, the absolute value of (in J mol) for the reaction at 300 K is . (Given; ln(2) = 0.7, = 2500 J mol at 300 K and is the Gibbs energy)