Một dụng cụ làm bằng thủy tinh dùng để đựng dung dịch có dạng hình nón với độ dài đường sinh là 15cm và diện tích xung quanh là 135π m2.Hãy tính thể tích của dụng cụ đó(bỏ qua bề dày của dụng cụ)

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