Use the fact that the loudness of sound (in decibels) perceived by the human ear depends on intensity levels according to L = 10 log(I/I0) where I0 is the threshold of hearing for the average human ear. A sound that causes pain has intensity about 1014 times I0. Find the decibel reading for this threshold.

you'd use the equation that establishes a relationship between  energy  and  wavelength, which looks like this

e=h⋅cλ, where

λ  - the wavelength of the photon; c  - the speed of light, usually given as  3⋅108m/s; h  -  planck's constant, equal to  6.626⋅10−34j s

plug the value you were given for the energy of the photon in the above equation to get the wavelength

e=h⋅cλ⇒λ=h⋅ce

λ=6.626⋅10−34js⋅3⋅108ms−1.257⋅10−24j=1.581⋅10−1m