
A.a/8
B.-a/4
C.a/2
D.a/10
[单选题]A.a/8B.-a/4C.a/2D.a/10
[单选题]等于( )。A.0B.9πC.3πD.(9/2)π
[单选题]=( )。A.B.C.D.0
[单选题]等于( )。A.0B.9πC.3πD.(9/2)π
[单选题]=( )。A.B.C.D.0
[单选题]等于( )。A.0B.9πC.3πD.(9/2)π
[单选题]=( )。A.B.C.D.0
[单选题]=( )。A.B.C.D.0
[单选题]=( )。A.B.C.D.0
[单选题]=( )。A.B.C.D.0