当要求在多处都可以开启和关断一台大型设备时要求（）。

答案查看网，轻松搜题/搜资源

【单选题】【消耗次数：1】

① 启动开关串联，关断开关串联

② 启动开关并联，关断开关串联

③ 启动开关和关断开关都并联

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