5and 3 over 4 subtracted from 3 and a half

Ihave a triangle with a 60 degree angle. lets use d for that angle. what are the values of e and f if d is 60 degrees? and what do you notice about the values of e and f?

Ineed on this question me get the answer

Awavelength of 610 nm was found to be the most intense wavelength emitted by copper. answer the following questions about this wavelength of light. a) what is this wavelength in cm? b) what is the frequency that corresponds to this wavelength? c) what is the energy of light of this wavelength? d) what is the wavenumber corresponding to this wavelength?