5 1 4 x 3 7 8 July 8, 2019 16 32 64 128 1 2 3 x 4 5 6 7 8 5 6 x 9 )+ 3 4 x 1 )- 7 9 8 5 3 4 x 1 8 x 7 8 grinding wheel 1 7 8 2 1 4 x 3 5 2 1 2 x 4 3 5 6 divided by 7 8 1 và 3 4 x 7 8 5 7 1 2 5 3 4 x 8 0 20
