— How much are they?
— fifty yuan. [ ]
A. It's
B. That's
C. They're
答案:C
变送器的误差是以()表示的
A.绝对误差
B.相对误差
C.引用误差
“一带一路”建设要加强供应链安全与便利化合作,推进跨境监管程序协调,推动()国际互联网核查,开展’经认证的经营者’(AEO)互认。
A.检验检疫证书
B.缴税证明
C.货物安全
D.海关签证