Formation of `NO_(2)F` from `NO_(2)` and `F_(2)` as per the reaction `2NO_(2)(g)+F_(2)(g)rarr2NO_(2)F(g)` is a second order reaction, first order with respect to `NO_(2)` and first order with respect to `F_(2)`. If `NO_(2)` and `F_(2)` are present in a closed vessel in ratio `2:1` maintained at a constant temperature with an initial total pressure of 3 atm, what will be the total pressure in the vessel after the reaction is complete?
A. 1 atm
B. 2 atm
C. `2.5` atm
D. 3 atm