One Type of Sunburn Occurs on Exposure to UV Light

One type of sunburn occurs on exposure to UV light of wavelength equal to 325 nm. What is the frequency given in sec ^{- 1} for this wavelength?

A) 1.08×10 ^{- 15} sec ^{- 1}
B) 9.23×10 ^{- 4} sec ^{- 1}
C) 9.75×10¹ sec ^{- 1}
D) 9.23×10⁵ sec ^{- 1}
E) 9.23×10¹⁴ sec ^{- 1}