15个圆锥可熔铸成几个和圆锥等底等高的圆柱请选择ABC-I+}7x+}/g3k5A-{:};|9o(N*L,k:r7\;V4{9z-R+E
A．5(N*L,k:r7\;V4{9z-R+E
B．15(N*L,k:r7\;V4{9z-R+E
C．45(N*L,k:r7\;V4{9z-R+E