图示电路中，稳压管的稳定电压U_z=6V，稳定电流I_z=5 mA。试求在稳定条件下I_L的数值最大不应超过（）。

A．55mA

B．-55mA

C．1mA

D．-1mA

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.

"Culture" refers to ______.

A．the book language of behavior we learn

B．the patterns of behavior we learn

C．traditional ideas

D．people’s good habits