人粪尿是一种养分含量高、肥效快的有机肥料。新鲜的人粪一般呈(),新鲜的尿液呈()
A、中性,中性
B、弱碱性,弱酸性
C、中性,弱酸性
D、弱酸性,弱碱性
参考答案:C
分解因式:a-ab2的结果是( )
A.a(1+b)(1-b)
B.a(1+b)2
C.a(1-b)2
D.(1-b)(1+b)
____ back home after the party.
A.It was not until midnight did he go
B.It was until midnight that he didn’t go
C.Not until midnight did he go
D.It was midnight that he didn’t go