包装粮表面惰性粉防虫时，根据粮堆面积按（）g/m2的用粉量。
A.0～2
B.2～5
C.10～15
D.5～10
参考答案：B
— What did she forget when she left for home?
— _____ the book.
[ ]
A. Taking
B. Took
C. Take
D. To take
海水中含量最多的物质是（ ）
A．NaCl
B．CaCO3
C．H2O
D．Mg（OH）2
