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
[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
[单选题]=( )。A.B.C.D.0
[单选题]A.0.5kN·m,上侧受拉B.0.5kN·m,下侧受拉C.1kN·m,上侧受拉D.1kN·m,下侧受拉
[单选题]等于( )。A.0B.9πC.3πD.(9/2)π