阅读理解。
Never before in history has a city been so completely destroyed. San Francisco is gone. Noting is left left of
it but memories and some houses far from the centre of the city. Its businesses are gone. The factories, hotels
and palaces are all gone too. Within an hour after the earthquake, the smoke of San Francisco's fires could be
seen a 160 kilometres away. The sun was red in the dark sky.There was no stopping the fires. There was no
way to organize or communicate.The steel railway tracks were now useless.And the great pipes for carrying
water under the streets had burst. All of the ways man had made to keep the city safe were gone in the thirty
seconds the earth moved.
Out at sea it was calm. No wind came up.Yet from every direction-east, west, north, and south, strong
winds blew upon the unlucky city. Man himself had to make ruins of some of the city's best buildings so that
they would not be a danger to those in the streets. A list of buildings not destroyes was now only a few
addresses. A list of the brave men and women would fill a library. A list of all those killed will never be made.
Amazing as it may seem, Wednesday night was a quiet night. There were no crowds.The policemen said
nothing; even their horses were quiet. There were no shouts or people doing crazy things. In all those terrible
hours I saw not one woman who cried, not one man who was excited.Before the fires, through the night,
thousands and thousands of people who had lost their homes left for safety. Some were covered in blankets.
Sometimes whole families put everything they owned and could save into wagons. They helped one another
climb the high hills around the city. Never in all San Francisco's history were her people so kind as on that
terrible night.
1. What's the main idea of the first paragraph? [ ]
A. San Francisco was destroyed worst in the history.
B. An earthquake hit San Francisco.
C.The smoke of San Francisco's fires could be seen a 160 kilometres away.
D. All of the ways were gone in the thirty seconds the earth moved.
2. Which of the following statements can be used to describe what happened in last paragraph? [ ]
A. It is always calm before a storm.
B. There's no smoke without fire.
C. Coming events cast their shadows before them.
D. When the city gate catches fire, the fish in the moat suffer.
3. What's the autor's feeling writing this article? [ ]
A. Happy.
B. Sad.
C. Excited.
D. Indifferent.
高处的斜面上静止释放，小球刚好能落到P点（sin37°＝0.6，cos37°＝0.8）。