For a reaction carried at 400 K,
`NO_(2)(g) + CO_(2)(g) to CO_(2)(g) + NO_(2)(g)`, the proposed mechanism is as follows:
`NO_(2) + NO_(2) overset("Slow")to NO + NO_(3) NO_(3) + CO overset("Fast")to CO_(2) + NO_(2)`
What is the rate law for the reaction?