Government investment has long held _____ leading role in stimulating (刺激) the nation's economy,

along with domestic consumption and exports. However, ____outlook for government investment this

year is not positive.[ ]

A. a; /    

B. a, an    

C. a, the    

D. the, the  

钢零件自由端火焰切割面无特殊要求的情况下，加工缺口度中缺口度为（）

A.1.0mm以下

B.1.5mm以下

C.2.0mm以下

D.3.0mm以下