在E-R图中，用来表示实体的图形是A．矩形 B．椭圆形 C．菱形 D．三角形

治疗肾阳虚微证水肿应选用的方剂是（）

A.实脾饮

B.真武汤

C.苓桂术甘汤

D.四君子汤

E.五苓散

净水器卫生安全性评价浸泡水水质卫生指标包括（）

A.感官性状指标、一般化学指标、毒理学指标和放射性指标

B.感官性状指标、毒理学指标、微生物指标和放射性指标

C.感官性状指标、一般化学指标、微生物指标和放射性指标

D.感官性状指标、一般化学指标、毒理学指标和微生物指标

E.一般化学指标、毒理学指标、微生物指标和放射性指标

根据有关营业税的规定，按期纳税的起征点为月营业额( )元。

A．1500～5000

B．1000～5000

C．2000～5000

D．2500～5000

Ⅰ级地质灾害应急响应的判别条件：（）

A.死亡30人及以上，或者100人以上重伤

B.直接经济损失（万元）≥10000

C.中断繁忙干线铁路行车48小时以上

D.国务院决定需要启动Ⅰ级应急响应的其他地质灾害

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