If the reaction $3$NO$2+2$O$()->$NO$+2$NO$3$ follows the mechanism,

$2$NO$2->$N$2$O$4-$ fast;

N$2$O$4+2$O$->$NO$2+$NO$3$ slow;

$2$NO$2->$ NO$+$ NO$2+2$O $$ fast.

What is the rate law? Molecularity? Order?