用电报装办(中心)收到批复的供电方案后,在()个工作日内书面通知客户。
A.1
B.2
C.3
D.4
参考答案:B
某一先张法预应力混凝土空心板,采用混凝土强度等级C50,采用预应力钢绞线1×7,其直径为d,σpe=1000MPa,当对该空心板端部区段进行正截面、斜截面抗裂验算时,其板端的预应力钢筋传递长度(mm),与下列何项数值最为接近()
A.60d
B.80d
C.55d
D.58d
一 Did you hear Tom was criticized for his spelling mistakes in his English composition?
一 Yes, but a more careful person _____ so many mistakes. [ ]
A. wouldn't make
B. needn't have made
C. shouldn't make
D. wouldn't have made