EVDO空中接口协议栈各层中，（）控制物理信道上数据的收发方式和消息的交互A.应用层
题型：单项选择题
问题：
EVDO空中接口协议栈各层中，（）控制物理信道上数据的收发方式和消息的交互
A.应用层
B.连接层
C.MAC层
D.物理层
题型：单项选择题
| 阅读理解。 |
 Dolphins are mammals, not fish. They are warm blooded like man, and give birth to one baby, called a calf, at a time. At birth, a bottlenose dolphin calf is about 90-130 cms long and will grow to approximately 4 metres, living up to 40 years. They are highly sociable animals, living in groups, called pods, which are fairly fluid, with dolphins from other pods interacting with each other from time to time. Dolphins carry their young inside their womb for about 12 months. The baby is born tail first, and its mother will feed the calf for up to 2 years. However, the calf will stay with its mother for between 3-6 years, during which time it will learn all about feeding techniques, social interaction and group hunting. |
| 1. What is a baby dolphin called? |
[ ] |
| A. A pod B. A baby C. A womb D. A calf |
| 2. How long does a dolphin calf stay with its mother? |
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| A. 12 months B. 2 years C. 3-6 years D. 40 years |
| 3. What kind of blood does a Dolphin have? |
[ ] |
| A. warm-blood B. cold-blood C. salt-water blood D. we don't know |
| 4. Which statement is Wrong? |
[ ] |
| A. Dolphins are living in groups. B. Dolphins lay eggs. C. Dolphins can live up to 40 years. D. Dolphins are not fish. |