钢丝墩头的强度不得低于钢丝强度标准值的89%。( )
参考答案:错
After several sleepless nights, Mr Johnson ________ a perfect solution to the financial problems of his
company. [ ]
A. came up with
B. put up with
C. kept up with
D. ended up with
铝材料与铜材料相比较,两者导电性能为()。
A.铝比铜好;
B.铜比铝好;
C.铜铝一样;
D.不一定。