液化石油气的爆炸上、下限分别是()。
A、2.15%;9.55%
B、2.25%;9.55%
C、2.15%;9.65%
D、2.25%;9.65%
参考答案:D
— Oh, that's just my missing pen. Where on earth was it?
— It _____ off the table into the corner. [ ]
A. has fallen
B. fell
C. falls
D. was falling
测定血清LDL-C的参考方法是 ()
A.定量法
B.二氯甲烷/硅酸/变色酸法
C.HPLC法
D.甘油磷酸氧化酶法
E.以上皆不是