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问题 选择题

下列说法正确的是

A．平行投影的投影线相交于一点,中心投影的投影线相交于一点

B．平行投影的投影线相交于一点,中心投影的投影线互相平行

C．平行投影的投影线互相平行,中心投影的投影线互相平行

D．平行投影的投影线互相平行,中心投影的投影线相交于一点

答案

答案：D

把在一束平行光线照射下形成的投影，，叫平行投影.平行投影的投影线互相平行；把光由一点向外散射形成的投影，叫做中心投影.中心投影的投影线交于一点；故选D

多项选择题

衡量财务报表及其所反映绞济活动合法性的标准是（）。

A.国家立法机关依照立法程序制定和颁布的法律

B.国家行政机关制定的法令、条例、规定

C.企业制定的生产经营计划

D.企业制定的材料消耗定额、工时定额

E.被审计单位上级主管部门和被审计单位内部制定的各项规章制度
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单项选择题

Scientists around the world are racing to learn how to rapidly diagnose, treat and stop the spread of a new, deadly disease. SARS — Severe Acute Respiratory Syndrome — was (1) for the first time in February 2003 in Hanoi, (2) since then has infected more than 1,600 people in 15 countries, killing 63. At this (3) , there are more questions than answers surrounding the disease.

Symptoms start (4) a fever over 100.4 degrees F, chills, headache or body (5) . Within a week, the patient has a dry cough, which might (6) to shortness of breath. In 10% to 200% of cases, patients require (7) ventilation to breathe. About 3.5% die from the disease. Symptoms (8) begin in two to seven days, but some reports suggest it (9) take as long as 10 days. Scientists are close to (10) a lab test to diagnose SARS. In the meantime, it is diagnosed by its symptoms. There is no evidence (11) antibiotics or anti-viral medicines help, (12) doctors can offer only supportive care. Patients with SARS are kept in isolation to reduce the risk of (13) . Scientists aren’t sure yet, but some researchers think it’s a (14) discovered coronavirus, the family of viruses that cause some common colds.

Most cases appear to have been passed (15) droplets expelled when infected patients cough or sneeze. Family members of infected people and medical workers who care for them have been most likely to (16) the illness. But recent developments in Hong Kong suggest that the (17) might spread through air, or that the virus might (18) for two to three hours on doorknobs or other (19) Health experts say it is (20) , though, that sharing an elevator briefly with an infected person would be enough to pass the virus.

8（）

A.regularly

B.ordinarily

C.traditionally

D.generally
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