Nevine wants to improve her javascript program's efficiency and scalability by defining her own processes, or functions. why are functions such an integral part of writing javascript code?

Light traveling in water, nwater = 1.33, strikes a plastic block at an angle of incidence of 51.4°; part of the beam is reflected and part is refracted. if the index of refraction of the plastic is 2.0, what is the angle made by the reflected and refracted beams?