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问题 选择题

下列实验操作，正确的是（　　）

A．用排空气法收集气体时，导管口要接近集气瓶底部

B．用50 mL水和50 mL酒精配制成100 mL酒精溶液

C．用量筒量取9.55 mL蒸馏水

D．用托盘天平称量时，将称量物放在右盘，砝码放在左盘

答案

A、用排空气法收集气体时，为防止集气瓶中的空气排不干净，造成收集的气体不纯，导管口要接近集气瓶底部，故选项说法正确．

B、由于分子间有间隔，用50mL水和50mL酒精配制成酒精溶液小于100mL，故选项说法错误．

C、用10mL量筒量取9.55mL蒸馏水，不符合10mL量筒的精确度为0.1mL，故无法量取，故选项说法错误．

D、托盘天平的使用要遵循“左物右码”的原则，用托盘天平称量时，将称量物放在左盘，砝码放在右盘，故选项说法错误．

故选A．

单项选择题

厥阴俞主治

A．心痛、心悸、咳嗽、胸闷、呕吐
B．呕吐、呃逆、气喘、吐血、贫血
C．心痛、惊悸、失眠、健忘、癫痫
D．胁痛、黄疸、目视不明
E．呕吐、腹泻、水肿、小便不利
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单项选择题

Most people would be (1) by the high quality of medicine (2) to most Americans. There is a lot of specialization, a great deal of (3) to the individual, a (4) amount of advanced technical equipment, and (5) effort not to make mistakes because of the financial risk which doctors and hospitals must (6) in the courts if they (7) things badly.

But the Americans are in a mess. The problem is the way in (8) health care is organized and (9) . (10) to pubic belief it is not just a free competition system. The private system has been joined a large public system, because private care was simply not (11) the less fortunate and the elderly.

But even with this huge public part of the system, (12) this year will eat up 84.5 billion dollars—more than 10 percent of the U. S. Budget—large number of Americans are left (13) . These include about half the 11 million unemployed and those who fail to meet the strict limits (14) income fixed by a government trying to make savings where it can.

The basic problem, however, is that there is no central control (15) the health system. There is no (16) to what doctors and hospitals charge for their services, other than what the public is able to pay. The number of doctors has shot up and prices have climbed. When faced with toothache, a sick child, or a heart attack, all the unfortunate persons concerned can do is (17) up. Two thirds of the population (18) covered by medical insurance. Doctors charge as much as they want (19) that the insurance company will pay the bill.

The rising cost of medicine in the U. S. A. is among the most worrying problems facing the country. In 1981 the country’s health bill climbed 15.9 percent--about twice as fast as prices (20) general.

4（）

A.countless

B.titanic

C.broad

D.vast
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