Try this solution:
the rule: if f1>f2, then E1>E2, where f1;f2 - frequency, E1;E2 - energy of light.
The formula is L=c/f, where L - the wavelength, c - 3*10⁸ m/s, f - frequency.
Frequency for the wavelength 519 nm. is:
[tex]f=\frac{c}{L}=\frac{3*10^8}{519*10^{-9}}=\frac{3*10^17}{519}=578034682080924=5.78*10^{14}( \frac{1}{sec})[/tex]
Answer: the energy of light of wavelength 519 nm.
