R:R: 3
R:R: 6
R:R: 2.4
R:R: 4
R:R: 2 khung h1
R:R:3 dời SL về hòa vôn skhi đc R:R: 1
R:R: 1,2
R:R:3
R:R: 2
R:R: 12
R:R: 5