For the Reaction 2 O₃ (G)→3 O₂ (G), Under a Given

For the reaction 2 O₃ (g) →3 O₂ (g) , under a given set of conditions the rate of appearance of O₂ is 6.1×10 ^{- 5} mol/L × s. What is the rate of the disappearance of O₃ under the same conditions?

A) 2.0×10 ^{- 5} mol/L × s
B) 4.1×10 ^{- 5} mol/L × s
C) 1.2×10 ^{- 4} mol/L × s
D) 6.1×10 ^{- 5} mol/L × s
E) none of these