起道作业一股钢轨起道时,一次作业起道量不得超过()mm,否则应通知供电部门调查确认接触网设备调整工作量并配合作业。
A.8
B.10
C.6
D.7
参考答案:D
焊接结构的优点之一是()。
A.能节省材料
B.焊接接头应力集中比较大
C.焊接结构刚性大
D.有较大的变形
Initially his book did not receive much attention, but two weeks after the critic’s review appeared in the newspapers, it climbed to the best sellers’ list.()
A. At first
B. First of all
C. At first sight
D. From the first