一般实验方法的回收率应该是()。
A.100%±1%
B.100%±2%
C.100%±3%
D.100%±4%
E.100%±5%
参考答案:E
Listen! They _______ in the next room. [ ]
A. are singing
B. is singing
C. are sing
D. sing
肺结核原发综合征不包括()
A.原发病灶
B.病灶周围炎
C.胸膜炎
D.淋巴管炎
E.淋巴结炎