一般而言，固定资产投资和流动资产投资之间存在一定的比例关系，经济发展水平越高，管理水

假设某旅馆业务规定，每张账单对应一个顾客，账单的发票号是唯一的，账单中包含顾客姓名、到达日期和顾客每日的消费明细，账单的格式如下表所示。

如果根据上述业务规则，设计一个关系模式：

R(发票号，到达日期，顾客姓名，消费日期，项目，金额)

试回答下列问题：

①找出R的候选键。

②判断R最高可达到第几范式，为什么

③给出R的一个可能的3NF分解。

One day, a tiger saw a frog(青蛙)． He had never seen a frog before． He said,“I want to eat you． But first tell me who you are．”

The frog said,“I’m the king(国王)of the frogs! I can do all kinds of wonderful things．”

“Really?” said the tiger．“Can you show me what you can do?”

“All right． Let’s jump across the river． I can jump longer than you．”answered the frog．

They came to the river, The tiger jumped across it． He was surprised to see the frog was in front of him．

“I’m waiting for you, Mr Tiger．”said the frog, laughing．

While the tiger was ready for his jump． the frog held(拉)the tiger’s tail(尾巴)and got some tiger’s hair in his mouth． But the tiger didn’t know．

“Why do you have some tiger’s hair in your mouth?”asked the tiger．

“Oh”．said the frog,“Yesterday I killed(杀)a tiger and ate him．”

After hearing that, the tiger ran away quickly．

小题1: What did the tiger want to do at first? He wanted to       ．

A． jump over

B． run a race(比赛)with the frog

C． eat the frog      

小题2: –What was the frog good at?        ．

A． Running．                   B． Jumping．              C． Eating．

小题3:Why was the tiger surprised? Because       ．

A． he found the frog was the king of the frog

B． the frog wanted to kill him

C． the frog also jumped across the river

小题4: How did the frog jump across the river? By    ．

A． waiting for the tiger

B． holding the tiger’s tail

C． eating the tiger’s hair

小题5:Who do you think is cleverer?

A． The tiger                 B． The frog              C． Neither

I'll ____________ ten books, please. [ ]

A. had

B. send

C. take

血清RF有IgG、IgA、IgM型。目前实验室采用散射比浊法检测的RF主要为

A．IgG

B．IgA

C．IgM

D．IgE

E．IgD

1979年钱钟书《管锥编》前四册问世是中国比较文学复兴的标志。