b. What was Oliver’s power in watts?
Answer:
D or 49.7°
Explanation:
You are given the equation and all the information you need, so you simply need to understand what the question asks for and answer appropriately. Notice that the light wave travels from the water to air. This means that water should be labelled with a "1" as it comes prior to air, which should be labeled "2". Thus, all you need to do, is plug and chug:
And, therefore, your answer is D, 49.7°.