2,2,0,7,9,9,( )
A.13;B.12;C.18;D.17;
0,1/9,2/27,1/27, ()A.27 B.7/9 C.5/18 D.4/243
0,1/9,2/27,1/27, () A.27 B.7/9 C.5/18 D.4/243
5, 7, 2, 9, 1,0, 1, ()。A.1 B.7 C.9 D.13
-7,0,1,2,9,()A.16B.28C.36 D.18
-7,0,1,2,() A.3 B.6 C.9 D.10
0,1/9,2/27,1/27,()。A.27B.7/9C.5/18D.4/243