叩诊可发现阳性体征的胸腔积液量为()。
A.200~250ml
B.150~200ml
C.300ml以上
D.100~150ml
E.100ml
参考答案:C
按要求改写句子。
1. There were many people there. (变为否定句)
There ______________ many people there.
2. I'm going by plane. (就画线部分提问)
______________ are you going?
铜线,钢芯铝绞线回路的特性阻抗近似值为()欧±10%。
A.170
B.600
C.1400
D.2000