please solve image reaction

 Dear Student,

Reaction : 2NO + Br₂ ---> 2NOBr

Mechanism :
NO + +  Br₂ $\iff$   NOBr₂(fast)

NOBr₂ + NO ----> 2NOBr (slow)

Rate law : K[NO]²[Br₂]

Order = Sum of the coefficient of the species involved in rate law = 1+ 2 = 3

Regards