不属于正常体液与组织中的抗菌物质是（） A.补体 B.溶菌酶 C.抗生素 D.乙型溶

The world is not hungry , but it is thirsty . It seems strange that nearly 3/4 of the earth is covered with water while we say we are short of water. Why? Because about 97% of water on the earth is sea water which we can't drink or use for watering plants directly. Man can only drink and use the 3% - the water that comes from rivers and lakes. And we can't even use all of that, because some of it has been polluted .

　　Now more water is needed. The problem is: Can we avoid (避免) a serious water shortage later on? First, we should all learn how to save water. Secondly, we should find out the ways to reuse it . Scientists have always been making studies in the field. Today, in most large cities water is used only once and then runs to the sea or rivers . But it can be used again. Even if every large city reused its water, still there would not be enough. What could people turn to next?

　　The sea seems to have the best answer. There is a lot of water in the sea. All that needs to be done is to get the salt out of the sea water. This is expensive, but it's already used in many parts of the world. Scientists are trying to find a cheaper way of doing it. So you see, if we can find a way out, we'll be in no danger of drying up.

小题1:The world is thirsty because ________.

A．3/4 of the earth is covered with water

B．we have enough sea water to use directly

C．we haven't used all the water in rivers and lakes

D．about 97% of water on the earth can't be drunk or used for watering plants directly小题2:Which of the following is true ?

A．3% of water on the earth is in rivers and lakes.

B．75% of water on the earth is the sea.

C．97% of the earth is covered with water.

D．3% of water on the earth is sea water.小题3:From the passage we learn _________.

A．if every city reuses its water, we'll be in no danger of drying up

B．man can only drink and use about 25% of water on the earth

C．today in most large cities water is used only once

D．water can be used only once小题4:To avoid the serious water shortage , which of the following is the most important?

A．Save water and try to make good use of the water in rivers and lakes.

B．Don't pollute water and keep all rivers and lakes clean.

C．Make dirty water clean and then reuse it.

D．Try to find a cheaper way to get the salt out of the sea water.小题5:The name of the passage would be ________

A．The Sea Water 　　　

B．How to Save Water　

C．The Thirsty World

D．The Polluted Water

— At present, one of the best ways to study is working in groups.

—More chances _______ to students to learn from each other.

A．offer

B．is offered

C．are offered

D．have offered

心电图上I和aVL导联出现急性心肌梗死的特异性改变,其梗死部位是心脏的

A．下壁

B．前壁

C．后壁

D．高侧壁

E．前间壁

下列有关审计抽样的说法中，错误的有（）。

A.注册会计师应当根据具体情况并运用职业判断，确定使用统计抽样或非统计抽样方法，以最有效率地获取审计证据

B.审计抽样适用于控制测试中的所有审计程序

C.统计抽样和非统计抽样方法的选用，在于对样本实施的审计程序

D.注册会计师采用不适当的审计程序可能导致抽样风险

下列关于出生率的叙述，正确的是（）

A.若某种群年初时的个体数为100，年末时为110，其中新生个体数为20，死亡个体数为10，则该种群的年出生率为10%

B.若某动物的婚配制为一雌一雄，生殖期个体的雌雄比例越接近1：1，则出生率越高

C.若通过调控环境条件，使某动物的性成熟推迟，则出生率会更高

D.若比较三种年龄结构类型的种群，则稳定型的出生率最高