In a study of nitrosyl halides, a chemist proposes the following mechanism for the synthesis of nitrosyl bromide:NO(g) + Br₂(g) ⇄ NOBr₂ (g) [fast}NOBr₂ (g) +NO(g) → 2NOBr(g) [slow]If the rate law is rate 5 k[NO]2[Br2], is the proposed mechanism valid? If so, show that it satisfies the three criteria for validity.