Reference no: EM13188191
(a) In the United States, _______ was the single most important form of energy from about 1890 until World War II, but ________ has been the most important since then. (Choose from: wood, petroleum, coal, gas, hydro, or nuclear.)
(b) Most of the earth's history is called the _______ Eon, but multi-cellular life left a distinct fossil record beginning about 550 million years ago.
(c) Since 1990, energy use per person has either remained fairly stagnant or has increased in different nations and regions of the world. Match the nation or region with the trend in energy use per person since about 1990. Column preview China
1. increasing energy use per person OECD nations
2. starting to see increases in energy use per person non-OECD nations
3. starting to see increases in energy use per person after 2000 World average
4. generally stagnant energy use per person