螺旋式千斤顶起重量5～32吨,顶升高度可达250～400mm。
参考答案：错
下列标准代号中， （14） 不是国家标准的代号。
A．GSB
B．GB/T
C．GB/Z
D．GA/T
We are pleased to know that you have planned to come to the Autumn Guangzhou Fair. We wish to discuss with you some other important things if you could come ______ your earliest convenience.
A．by B．onC．in D．at
