计量员根据计量仪器检定规程选择符合条件的国家法定机构，（）进行送检。
参考答案：依据量值溯源图
Studying abroad costs so much money that it is the reach of those with average income．
A．below
B．over
C．within
D．beyond
偏航系统的主要作用有哪两个？
