煤矿的()等安全设备、设施和条件应符合国家标准、行业标准。
A.通风
B.防瓦斯
C.防煤尘
D.防水火
E.环境卫生
参考答案:A, B, C, D
不用电池点火,打开热水器的水龙头,就有源源不断的热水流出….如图所示展示的是2012年重庆市第27届青少年科技创新大赛中我市一名中学生的发明--燃气热水器水流供电打火装置.这个装置可以让燃气热水器再也不用电池,既省钱又环保.
据发明者介绍,他制作了一个“水流发电机”放在热水器的入水口,里面有一个涡轮.当自来水冲击涡轮转动时,转动的涡轮带动小型发电机发电,电压可达3V,供给热水器点火装置完成点火.请参照示例写出这种热水器在使用过程中所涉及的物理现象和对应的物理知识(不得与示例重复).
示例:物理现象:燃气燃烧
物理知识:化学能转化为内能
作答:物理现象:______;
物理知识:______.
Do animals have a culture What do we mean by "culture" Lately social scientists have begun to ask if culture is found just in humans, or if some animals have a culture too. When we speak of culture, we mean a way of life a group of people have in common. Culture includes the beliefs and attitudes we learn. It is the patterns of behavior that help people to live together. It is also the patterns of behavior that make one group of people different from another group. Our culture lets us make up for having lost out strength, claws, long teeth, and other defenses. Instead we use tools, cooperate with one another, and communicate with language. But these aspects of human behavior, or "culture," can also be found in the lives of certain animals. Animals can make tools, for example. We used to think that the ability to use tools was the dividing line between human beings and other animals. Lately, however, we have found that this is not the case. Chimpanzees(黑猩猩) can not only use tools but actually make tools themselves. Animals can also share knowledge with each other and use their own language to communicate. So it may be important for us to know that the line dividing us from animals is not as clear as we used to think.
Which of the following statement is TRUE
A.The ability to use language separates human beings.
B.We can be certain that animals have a culture too.
C.Social scientists doubt if animals have a culture too.
D.Some traditional ideas about the difference between human beings and animals may be wron