阅读理解
NEWS --- reported in the New York News.
WORSE BUSH FIRE OF CENTURY PUTS SOUTHERN AUSTRALIAN TOWNS IN DANGER
No one knows yet the number of lives which have been lost in this terrible fire. But reports say that
more than a hundred people have died.
Towns less than one hundred miles from Melbourne will be in danger unless the wind changes. The
edge of the smoke cloud has already reached Melbourne. People are rushing into the streets. The police
have warned them not to drive out of the city to see the fire, but many people are doing so.
The cause of the fire is unknown. But nobody is surprised. No rain has fallen in this part for three
months. It is 38℃ at noon, and the hot northwest wind from the great central desert is blowing at more
than thirty miles an hour.
1. The big fire happened in ______.
A. New York
B. a place near Melbourne
C. towns in Melbourne
D. town in America
2. We can see from the news that ______.
A. people there haven't seen such a big fire for nearly 100 years
B. no one knows whether some people have died in the fire or not
C. everyone knows the cause of the fire
D. most of the towns in the country are in danger
3. Which of the following is the right picture?
W=WindT=TownsM=Melbourn
圆管轨道，其半径为R=0.5m，内径很小。平台高h="1.9" m，一质量m=0.5kg、直径略小于圆管内径的小球，从平台边缘的A处水平射出，恰能沿圆管轨道上P点的切线方向进入圆管内，轨道半径OP与竖直线的夹角为3
7°。g＝10m/s2，sin37°＝0.6，cos37°＝0.8。不计空气阻力。求：