答案:83
A. (A)110V
B. (B)440V
C. (C)220V
D. (D)50V
A. (A)泄露现象
B. (B)摩擦阻力
C. (C)流量损失
D. (D)压力损失
A. (A)4000mm
B. (B)4600mm
C. (C)4800mm
D. (D)5000mm