10Washing and drying the bulk raw material to prevent spoilage also isn’t easy. During WWII, volunteers in Britain occasionally dammed natural streams to wash the seaweeds and used hot air from a bakery to dry them. Praising the concerted efforts of volunteers, the UK Ministry of Supply concluded that “all belligerent countries should have a local source” of agar.
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（三）在铁路、城市轨道交通线路、桥梁、隧道、涵洞处挖掘坑穴、采石取沙的；
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