HINH VE DUNG SOAN GA 9

  ⊕ G N S N S N S K B A K S  N S N S N S  N S N S N S - + + K R A V R A V C K + - R d + - Đ K A C K V A C + - A V K A 32 1 A V A K A V A V V I i r N S N’ K O F’F B’ A B A K. khí Nước S N I H E G NĐ è’