【简答题】设 ,用复合函数求导法及隐函数公式法求 .
【判断题】脉冲充电方式可以有效的减少极板硫化现象,保护蓄电池的寿命
【简答题】It is well-known that _______________is the top number taboo of English-speaking countries.
【简答题】It is well known that China is a country with rich natural ___________ and a very big population.
【单选题】在发动机控制中,能影响被控对象的工作过程,用来改变被控参数大小的因素被称为:
【单选题】两个单片机之间采用RS232接口,进行数据交换(收、发),至少需要连接( )条线