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问题 选择题

下列关于金属的物理性质和用途描述中不正确的是（　　）

A．钢铁的硬度大，可作菜刀

B．金有金属光泽，是黄色，可做首饰

C．钨丝的熔点高，可作灯丝

D．银的导电性好，广泛用作电线

答案

A、钢铁的硬度大，所以可以用来制作菜刀，故A描述正确；

B、金的金属光泽为金黄色，所以可以用来制作首饰，故B描述正确；

C、灯丝通电后温度较高，所以需要熔点高的金属，而钨丝的熔点高，所以可以用来制作灯丝，故C描述正确；

D、银的导电性虽然好，但是由于其价格较高，故不适合制作电线，故D描述不正确．

故选D．

多项选择题

下面关于石狮子的描述正确的是( )。

A．起到辟邪的作用

B．显示尊贵和威严

C．摆放位置为左雌右雄

D．北狮活泼，南狮威严

E．有狮子所蹲之石上雕着凤凰和牡丹的三王狮
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单项选择题

The war for independence from Britain was a long and economically costly conflict. The New England fishing industry was temporarily destroyed, and the tobacco colonies in the South were also hard hit. The trade in imports was severely affected, since the war was fought against the country that had previously monopolized the colonies’ supply of manufactured goods. The most serious consequences were felt in the cities, whose existence depended on commercial activity. Boston, New York, Philadelphia, and Charleston were all occupied for a time by British troops. Even when the troops had left, British ships lurked in the harbors and continued to disrupt trade.　　American income from shipbuilding and commerce declined abruptly, undermining the entire economy of the urban areas. The decline in trade brought a fall in the American standard of living. Unemployed shipwrights, dock laborers, and coopers drifted off to find work on farms and in small villages. Some of them joined the Continental army, or if they were loyal to Britain, they departed with the British forces. The population of the New York City declined from 21,000 in 1774 to less than half that number only nine years later in 1783.　　The disruptions produced by the fighting of the war, by the loss of established markets for manufactured goods, by the loss of sources of credit, and by the lack of new investment all created a period of economic stagnation that lasted for the next twenty years.

Why does the author mention the population of New York City in paragraph 2

A．to show that half of New York remained loyal to Britain

B．to compare New York with other cities occupied during the war

C．to emphasize the great short-term cost of the war for New York

D．to illustrate the percentage of homeless people in New York
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