如图所示电路,求电压Uab()
A.Uab=7V
B.Uab=6V
C.Uab=5V
D.Uab=4V
参考答案:A
We must make ___ to the public that something should be done to stop pollution.
A.what is clear
B.it is clear
C.it clear
D.that clear
钢材经淬火后,强度和硬度(),脆性(增大),塑性和韧性明显降低。