BG1-300型变压器一次侧额定电流为()A。 ["0.25","0.17","1.8","3.6"]
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IKE主模式下经历三个阶段,在()阶段产生密钥。 ["策略协商","DH交换","ID交换","ID验证"]
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何谓玻璃的介电损耗?