桥式整流电路中，某电流正半周时要通过（）只二极管。
A.1
B.2
C.3
D.4
参考答案：B
Experiments have shown that 160 decibels of noise are lethal for small fur-bearing animals.
A．protective
B．deadly
C．harmful
D．deafening
铂热电阻有何特点？
