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问题 填空题

就地启车前检查破碎机各个（）以及侧板、齿板、边齿板的固定螺栓是否松动，确认运转灵活。待下道工序设备运转正常后，方可起动破碎。

答案

参考答案：运转部位

单项选择题

生产经营单位新建、改建、扩建工程项目的安全设施，必须与主体工程( )。

A．同时设计、同时施工、同时投入生产和使用
B．同时设计、同时施工、同时竣工
C．同时设计、同时招标、同时施工
D．同时招标、同时施工、同时投入生产和使用
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单项选择题

Questions 81-90 are based on the following passage.


It sounds like a science fiction, but researchers say it’s a scientific fact: Microscopic organisms dubbed "killer algae" are paralyzing fish with unknown toxins and then eating away at their flesh. They might be making people sick, too.
The name given to this single-cell organism, or dinoflagellate, is Pfiesteria piscimorte- literally, "fish killer. " It was discovered at North Carolina State University in 1988, but at the same time, few scientists believed in its existence, much less in its highly unusual predatory nature. But ongoing research has led to international acknowledgment of the phenomenon and, recently, research funding.
Seemingly prompted by an unknown substance secreted by fish, the aggressive creature swims into action. It sends neurotoxins into the water and air, paralyzing a fish’s nervous system, and causing it to gasp for air at the surface. Eventually the fish suffocates. The killer dinoflagellate then attaches itself to the fish and begins sucking away at its flesh. This macabre scenario may help solve several sea mysteries, such as why fishermen report seeing "fish walks" (fish trying to leave the water) and pools of dead fish with holes eaten through them.
Whether humans are affected by the dinoflagellate’s toxin remains to be seen. Researchers think it’s unlikely eating fresh fish are in danger, but anyone with frequent exposure to the creature could be in peril. Several researchers working with the algae have reported bouts of memory loss and disorientation.
To understand the killer algae further, scientists must fully characterize their toxin and determine what stimulates them to attack. They also need to know if the algae are hurting fish populations, and whether pollutants make them more likely to attack.

The word "they" underlined in Paragraph 1 refers to ______.

A. organisms
B. fish

C. toxins

D. flesh
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