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问题 选择题

面粉生产车间必须严禁吸烟，主要目的是（　　）

A．保护工人健康

B．避免烟尘杂入面粉

C．防止污染环境

D．防止发生爆炸

答案

面粉生产车间中漂浮很多面粉颗粒，面粉颗粒是可燃物，当与空气混合时遇到明火会发生爆炸，故要严禁烟火．

故选D

单项选择题

既能治疗肺虚久咳，又能治疗新咳的药为

A．浙贝母

B．百部

C．川贝母

D．紫菀
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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.

Which of the following questions is answered according to the information given in the passage

A. What is the toxin used by the fish killer
B. Who first discovered the organism
C. How does the fish killer paralyze fish
D. How many fishes can the organism kill each day
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