$ {NO_2}$ required for a reaction is produced by the decomposition of $ {N2O5}$ in $ {CCl4}$ as per the equation
$ { 2N2O5(g) -> 4NO2(g) + O2(g).}$
The initial concentration of $ {N2O5}$ is $3.00\, mol$ $ {L^{-1}}$ and it is $2.75\, mol$ $ {L^{-1}}$ after $30$ minutes. The rate of formation of $ {NO2}$ is :