丈量某长方形的长为a=20±0.004m,宽为b=15±0.003m,则它们的丈量精度()。
A.相同
B.不同
C.不能进行比较
D.以上都不对
参考答案:A
向西走10米记作-10米.从A地先走12米,再走-15米,现在这人在向______米.
At present, the Chinese government is _____ a great many experts who have mastered the rules
of the WTO. [ ]
A. calling on
B. calling for
C. calling at
D. calling up