E1线的阻抗类型有()。
A.50欧
B.75欧
C.100欧
D.120欧
参考答案:B, D
They look the same they are very different.[ ]
A. and
B. so
C. because
D. but
头箍式头花将花材加工成()形。
A、圆球
B、花环
C、水滴
D、弯月