The Equilibrium Constant for the Following Gas-Phase Reaction Is 68

The equilibrium constant for the following gas-phase reaction is 68.0.
2 IBr(g) I₂(g) + Br₂(g)
At equilibrium, twice as much Br₂ is present as IBr and the partial pressure of I₂ is 1 atm. What is the equilibrium partial pressure of IBr?

A) 0.0074 atm
B) 0.0037 atm
C) 0.029 atm
D) 0.059 atm
E) 136 atm