第30题: [单项选择]RS-232,RS-485接口是什么样的接口() A. 均为标准串行接口 B. 均为标准并行接口 C. 前者为串行,后者为并行接口 D. 前者为并行,后者为串行接口 参考答案:A
第31题: [单项选择]May I borrow your dictionary for a minute() A. Sure. Here you are. B. The dictionary is very expensive. C. The dictionary is very useful. D. Thank you very much. 参考答案:A