[单项选择]

Passage Five Temperatures on December 12 City High Low Cleveland .................. 37° 31° Columbia, S. C ............ 60° 27° Columbus, Ohio ............ 41° 34° Dallas .................... 81° 50° Dayton. ................... 41° 33° Decatur ................... 39° 30° Denver .................... 49° 33° Des Moines ................ 34° 27° Detroit ................... 37° 28° Dubuque ................... 30° 23° Duluth .................... 19° 10° Eau Claire ................ 24° 19° El Paso ................... 79° 36° Evansville ................ 52° 36° Fairbanks ................. -31° -40° Fargo ..................... 17° -2° Flint ..................... 31° 26° Flagstaff ................. 56° 31° Great Falls ............... 14° 3° Grand Rapids .............. 33° 26° Green Ray ................. 24°
A. 26°.
B. -2°.
C. 3°.
D. 31°.

Passage Five Temperatures on December 12 City High Low Cleveland .................. 37° 31° Columbia, S. C ............ 60° 27° Columbus, Ohio ............ 41° 34° Dallas .................... 81° 50° Dayton. ................... 41° 33° Decatur ................... 39° 30° Denver .................... 49° 33° Des Moines ................ 34° 27° Detroit ................... 37° 28° Dubuque ................... 30° 23° Duluth .................... 19° 10° Eau Claire ................ 24° 19° El Paso ................... 79° 36° Evansville ................ 52° 36° Fairbanks ................. -31° -40° Fargo ..................... 17° -2° Flint ..................... 31° 26° Flagstaff ................. 56° 31° Great Falls ............... 14° 3° Grand Rapids .............. 33° 26° Green Ray ................. 24°
A. 81°.
B. 50°.
C. 41°.
D. 60°.

Passage Five
Temperatures on December 12
City High Low
Cleveland .................. 37° 31°
Columbia, S. C ............ 60° 27°
Columbus, Ohio ............ 41° 34°
Dallas .................... 81° 50°
Dayton. ................... 41° 33°
Decatur ................... 39° 30°
Denver .................... 49° 33°
Des Moines ................ 34° 27°
Detroit ................... 37° 28°
Dubuque ................... 30° 23°
Duluth .................... 19° 10°
Eau Claire ................ 24° 19°
El Paso ................... 79° 36°
Evansville ................ 52° 36°
Fairbanks ................. -31° -40°
Fargo ..................... 17° -2°
Flint ..................... 31° 26°
Flagsta
A. 81°.
B. 50°.
C. 41°.
D. 60°.

Passage Five
Scientists claim that air pollution causes a decline in the world’ s average air temperature. In order to prove that theory, ecologists have turned to historical data in relation to especially huge volcanic eruptions. They suspect that volcanoes effect weather changes that are similar to air pollution.
One source of information is the effect of the eruption of Tambora, a volcano in Sumbawa, the Dutch East Indies ( the former name of the Republic of Indonesia) ,in April 1815. The largest recorded volcanic eruption, Tambora threw 150 million ton of fine ash into the stratosphere. The ash from a volcano spreads worldwide in a few days and remains in the air for years. Its effect is to turn in coming solar radiation into space and thus cool the earth. For example, records of weather in Eng land show that between April and November 1815, the average temperature had fallen 4.5°F during the next twenty-four months, England suffered one of th
A. Weakened
B. Improved
C. Depreciated
D. Declined