An Argon Ion Laser Emits Light at 489 Nm

An argon ion laser emits light at 489 nm. What is the frequency of this radiation?

A) 147 sec ^{- 1}
B) 6.13×10⁵ sec ^{- 1}
C) 1.47×10¹¹ sec ^{- 1}
D) 6.13×10¹⁴ sec ^{- 1}
E) None of these