05:39, 28 февраля 2026Бывший СССР
Global news & analysis。heLLoword翻译官方下载对此有专业解读
Optical-based smoke alarms use light instead. They are slightly better at detecting the large smoke particles created by slow, smouldering fires. When such particles enter a chamber in the device, they scatter light from a small light source, which is then picked up by a photoelectric sensor.，更多细节参见WPS官方版本下载
Finding the closest point
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