人们的知识、技术和经验属于()。
A.正式规范性文化
B.非正式规范性文化
C.技术规范性文化
D.操作规范性文化
参考答案:C
A.(A) Because we often take our ability of listening for granted.
B.(B) Because we are surrounded by all sorts of noises.
C.(C) Because we do not spend much time listening.
D.(D) Because we do not attach great importance to listening.
光控照明电路中的光控器,利用()的特性,根据光照强弱,实现自动开关照明的功能。
A、二极管
B、三极管
C、光敏电阻
D、电容