从混凝土组成材料的质量和比例而言,影响混凝土强度的主要因素有()。
A、灰水比;
B、粗集料品种;
C、水泥品种;
D、水泥强度。
参考答案:B, C, D
—I haven’t finished my essay because the computer broke down when I was downloading the required data last night.
—Really! You could have turned to me. I mine.
A.didn’t use
B.won’t use
C.hadn’t used
D.wasn’t using
《气象仪器和观测方法指南》一书中,通常将少于()mm的降水作为微量降水。
A.0.0
B.0.1
C.0.2
D.0.5