下列词语中，加粗字的读音全都正确的一项是[ ] A．濡缕（rú）杯杓（sháo）叱

出口打火机．点火枪类商品生产企业向所在地检验检疫机构提交书面登记申请，并提供有关的资料，经考核不合格的企业，整改后可申请复核，经复核仍不合格，（）才能重新申请。

A.半年后

B.1年后

C.3个月

D.1个月

根据估计的总销售收入和估计的销售量来制定价格的定价方法是()

A．目标定价法

B．成本加成定价法

C．随行就市定价法

D．价值定价法

水溶性涂饰涂料具有的优点是______。 Ⅰ．附着力强 Ⅱ．省丁省料 Ⅲ．维修方便 Ⅳ．耐老化 Ⅴ．施工效率高

A．Ⅰ、Ⅲ、Ⅴ

B．Ⅱ、Ⅳ、Ⅴ

C．Ⅲ、Ⅳ、Ⅴ

D．Ⅱ、Ⅲ、Ⅴ

All animals must rest, but do they really sleep as we know it The answer to this question seems obvious. If an animal regularly stops its activities and stays quiet and unmoving—if it looks as though it is sleeping—then why not simply assume that it is in fact sleeping But how can observers be sure that an animal is sleeping

They can watch the animal and notice whether its eyes are open or closed, whether it is active or lying quietly, and whether it responds to light or sound. These factors are important clues, but they often are not enough. Horses and cows, for example, rarely close their eyes, and fish and snakes cannot close them. Yet this does not necessarily mean that they do not sleep. Have you ever seen a cat dozing with an eye partly open Even humans have occasionally been observed to sleep with one or both eyes partially open. Animals do not necessarily lie down to sleep either. Elephants, for example, often sleep standing up, with their tusks resting in the fork of a tree. Finally, while "sleeping" animals often seem unaware of changes in the sounds and light and other stimuli around them, that does not really prove they are sleeping either.

Observations of animal behavior alone cannot fully answer the question of whether or not animals sleep. The answers come from doing experiments in "sleep laboratories" using a machine called the electroencephalograph (EEC). The machine is connected to animals and measures their brain signals, breathing, heartbeat, and muscle activity. The measurements are different when the animals appear to be sleeping than when they appear to be awake. Using the EEC, scientists have confirmed that all birds and mammals studied in laboratories do sleep. There is some evidence that reptiles, such as snakes and turtles, do not truly sleep, although they do have periods of rest each day, in which they are quiet and unmoving. They also have discovered that some animals, like chimpanzees, cats, and moles (who live underground), are good sleepers while others, like sheep, goats, and donkeys, are poor sleepers. Interestingly, the good sleepers are nearly all hunters with resting places that are safe from their enemies. Nearly all the poor sleepers are animals hunted by other animals: they must always be watching for enemies, even when they are resting.

How can researchers in "sleep laboratories" tell that the animals they are observing are asleep or not（）

A. They see if the animals respond to light and sound

B. They do this by observing changes in the animals’ brain signals, breathing, heartbeat, and muscle activity

C. They see if the animals’ eyes are closed

D. They can tell this by seeing if the animals lie down or not

封闭火区的防火墙，瓦斯急剧变化时，每班至少检查（）次。

A、1

B、2

C、3

D、4