co 1 cai can 10 lit va 1 can 20 lit trong moi can dung 1 luong dau khong ro la bao nhieu .neu do dau tu can lon sang can be cho day thi so dau con lai trong can lon =6/7 luong dau luc dau neu do tu can nho sang can lon cho day thi can nho con lai 2 lit .hoi luc dau moi can bao nhieu lit