卵磷脂对油脂的乳化作用很强，可用作（）用乳剂的乳化剂。
参考答案：静脉注射
—__________ are those pants?
—They are 100 yuan.
A．How many
B．How much
C．What
D．How
X线管的靶面材料通常是
A．铁 B．钨 C．金D．铜 E．钼
