When an electron moves to another orbital farther from the nucleus, does it gain or lose energy?

Does anyone know a lot about how to: - calculate mass of magnesium metal - calculate the actual yield of magnesium oxide - calculate the theoretical yield of mgo - calculate the percent yield of mgo - determine the percent yield of mgo - determine the average percent yield of mgo i had to do an online lab and its asking these questions but i have no idea where to start or how to be able to find these things. i can post the chart of the data from the lab or if you can tell me exactly how i can find each.

Stage in which a typical star has completely stopped fusion

What causes different colors to appear in the sky? the absorption of light by air molecules the reflection of light by bodies of water the greenhouse effect in earth's atmosphere the scattering and reflection of light by dust particles