How does friction impact work? (that's the whole question)

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?

Examples of states of consciousness include a. daydreaming b. dreaming during sleep c. hypnosis d. all of the above

Which symbol in the first law of thermodynamics represents the sum of the chemical and thermal energy stored in atoms and molecules? a. q b.w c.v d.u