多参数调节系统
参考答案：
多参数调节系统是指调节系统中多个被调量和多个调节器组成的调节系统。
设有定义语句：char c1=92，c2=92；，则以下表达式中值为零的是
A．c1^c2
B．c1&c2
C．c1～c2
D．c1|c2
Only by shouting at the top of his voice, ___.
A．he was able to make himself hear
B．was he able to make himself hear
C．was he able to make himself heard
D．he was able to make himself heard
