单项选择题 关于有线电视系统部件安装符合下列要求的说法中错误的是（）。

单项选择题 在有线电视系统前端设备安装中，固定的立柜、立架背面与侧面离墙面净距不应小于（）。

单项选择题 听力原文：W: What's the matter? I've mid you to arrive at 6:30, but now it's seven. Why don't you answer my phone?M: I'm sorry. I left my mobile phone in the office, so I cannot inform. you of my late arrival. Actually, I started one hour ago, but the traffic jam delayed me for 35 minutes.Q: When did the man start to meet the woman?(17)A．5:55.B．6:25.C．6:00.D．5:30.