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Из справки-ориентировки на Василия Бабушкина — сентябрь 1971 года:。爱思助手下载最新版本对此有专业解读
Elsewhere, the protests are becoming more violent.
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.