设函数z=ln(xy),则
参考答案:A
Which Inmarsat system applies store-and-forward messaging?()
A.Inmarsat-A
B.Inmarsat-C
C.Inmarsat-B
D.Inmarsat-M
脑动脉粥样硬化好发于什么动脉?有哪些严重后果?