—Where is Changsha?
—It's in _________. [ ]
A. Beijing
B. Hubei
C. Hebei
D. Hunan
答案:D
hsrp的组播地址为().
A.224.0.0.18
B.224.0.0.2
C.224.0.0.9
D.224.0.0.10
已知一个正数的平方根是3x-2和5x+6,则这个数是_______.