Max whirls a 0.5 kg bucket of Mountain Dew at the end of a string of length r = 0.3 m in a vertical circle. At the top of the path, the bucket’s speed is the minimum value such that the Mountain Dew does not fall out of the bucket. What is the tension in the string at this point? a) 10 N
b) 2.2 N
c) 1.7 N
d) 0 N

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