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bahien164
2 năm trước
Trộn lẫn rượu và nước , người ta được 1 hỗn hợp có khối lượng 138gam ở 30 độ C , Tính khối lượng của rượu và nước đã pha , biết rằng rượu có nhiệt độ là 20 độ C , nước có nhiệt độ là 80 độ C , biết nhiệt dung riệng của rượu là 2500J/KG.K , nước là 4200 J/KG.K . Bỏ qua sự bốc hơi của rượu
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