若点 P(a,a-2)在第四象限,则a的取值范围是( ).
A:-2<a<0
B:0<a<2
C:a>2
D:a<0
A.煤炭直接燃烧 B.秸秆焚烧还田
C.开发清洁能源 D.____;
—Is that all?
—Yes. That's all ______ I want to take.
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