At 225 degrees Celsius nitrogen dioxide NO2 reacts with carbon monoxide CO to produce carbon dioxide CO2 and nitrogen monoxide NO according to the following equation.NO2(g) CO(g) = CO2(g) NO(g)The experimentally determined rate law for the reaction is Rate=kobs[NO2]^2and NO3(g) has been experimentally identified as an intermediate in the reaction.a.) Explain why the mechanism for this reaction CANNOT consist of a single step; that is based on the experimental data provided above why must the reaction mechanism involve more than one step?b.) Assuming that the reaction mechanism does NOT involve a fast pre-equilibrium step propose a two-step mechanism for this reaction that satisfies the two tests discussed in lecture and explain your reasoning.