CDMA采用了扩频调制和码分多址有诸多优点大容量（）高话音质量和低发射功率，话音激活和保密性好。
参考答案：软容量、软切换
____________ from other continents for millions of years,Australia has many plants and animals not found in any other country in the world.
A Being separated B Having separated C Having been separated D To be separated
202.16.10.6的缺省子网掩码是（）
A.255.255.0.0
B.255.255.255.0
C.255.255.255.240
D.255.255.255.255
