Passage Three
All the useful energy at the surface of the earth comes from the activity of the sun. The sun heats and feeds mankind. Each year it provides men with two hundred million tons of grain and nearly ten million tons of wood.
Coal, oil, natural gas, and all other fuels are stored-up energy from the sun. Some was collect ed by this season’s plants as carbon compounds. Some was stored by plants and trees ages ago.
Even waterpower derives from the sun. Water turned into vapor by the sun falls as rain. It courses down the mountains and is converted to electric power.
Light transmits only the energy that comes from the sun’ s outer layers, and much of this energy that is directed toward the earth never arrives. About nine-tenths of it is absorbed by the atmosphere of the earth. In fact; the earth itself gets only one half-billionth of the sun’ s entire output of radiant energy.
Passage Three
All whales fall into two groups, those with teeth and those without. Both beluga and dolphin belong to the suborder of toothed whales known as Odontoceti, along with porpoises, narwhals, pilot whales, killer whales and the largest toothed creature in the world, the sperm whale. Size differences among the Odontoceti are remarkable. A common porpoise will run only 4 or 5 feet in length and 300 pounds in weight; a sperm whale may be 10 times as long and 300 times as heavy. The beluga falls in between, weighing up to 2,000 pounds. And it does chirp. In fact, it makes a great variety of squeaking, whistling, and clicking sounds, which have earned it the name of sea canary.
The toothless, or baleen, whales belong to the suborder of Mysticeti. This is a group of generally large whales, formerly abundant in all the oceans of the world. Though reduced by hunting, most species are still found along the coasts of the United Stated and Canada. All but two
A. a bird
B. a giant
C. an elephant
D. a submarine
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