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幼苗
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In order to deliver food and medicine miners,rescue workers also designed a called "Prynne Dove" rescue equipment.This is a 5 inch (collectively 12.7 cm) long,hollow cylinder,the working principle similar to the pneumatic tube.Rescue workers to "Prynne Dove" is loaded with supplies,then sent to the miners through the ventilation pipe shelter.
1年前
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