3, 9, 6, 9, 27, (), 27。
A.15
B.18
C.24
D.30
4,5,15,6,7,35,8,9,() A.27 B.15 C.72 D.63
15,5,3,5/3,______ () A.9/5 B.27/5 C.15/9 D.9/15
4,5,15,6,7,35,8,9,()A.27 B.15C.72D.63
-1,1,1,3,3,9,5,()A.5 B.9 C.15 D.27
3, 9, 6, 9, 27, ?, 27A. 15B. 18C. 20D. 30
27 15 12 () 9 -6。A.10 B.7 C.5 D.3