移频闭塞分区的长度大于移频轨道电路极限长度时，应增设（）点。

根据短文内容,判断句子的正(T)误(F).

     Water is very important for living things. Without water there can be no life on the earth. All plants

and animals need water. Man also needs water. We need water to drink, to cook food and to clean

ourselves. Water is needed in farms, factories, offices, schools and families.

     Water is found in seas, rivers and lakes. It can be found everywhere in the world, and it can also be

found in the air. We cannot see or feel the water when it is part of air. Clouds are also made of water.

They are little drops of water. When water freezes (冻结), it is ice. So ice is also water.

( )1. Some living things can live without water.

( )2. Man needs more water than the other living things.

( )3. Water can be found on the earth and in the air.

( )4. Clouds are made of very little drops of water.

( )5. Water changes into ice when it freezes.

侦察卫星可以发现地面上边长仅为0．36 m的方形物体，而卫星距离地面高度仅有十几千米．理论和实践都表明侦查卫星离地面越近，它的分辨率就越高．那么分辨率越高的侦查卫星（　　）

A．它的运行速度一定越小　

B．它的运行角速度一定越小

C．它的环绕周期一定越小　

D．它的向心加速度一定越小

下列对沙尘暴的解释，最准确的一项是 ( )

A．沙尘暴是由于风将大量沙尘卷起，使空气混浊，能见度小于千米的风沙天气现象。

B．沙尘暴是雕塑大地外貌的自然力之一，是大自然保持全球生态平衡的一项工程。

C．从地质史上看，沙尘暴是风力对草原带的风化物质进行筛选分类的结果。

D．沙尘暴是那些颗粒中的粗砂和细砂被大风吹移到附近就地聚集成沙漠形成的。

食品，含牛肉15%，茄子55%，鱼块25%，猪肉5%

在使用调脂药的过程中发生了不良反应，患者应采取的措施是：（）

A、停药

B、请医生诊治

C、更换调脂药

D、不停调脂药，对症治疗