确诊骨肉瘤的依据( )
A．血碱性磷酸酯酶测定B．血管造影C．X线拍片D．活组织检查E．临床表现
参考答案：D
Whenever a big company ______ a small one, the product almost always gets worse.
A．gets on with.
B．cuts down
C．takes over
D．puts up with
电感滤波器通常（）在电路中。
A、并联
B、串联
C、先并联后串联
D、先串联后并联
