下列程序段的执行结果为（ ）。　　a=3　　b=1　　For I=1 To 3

当投资者改变了对风险和回报的态度，或者其预测发生了变化，投资者可能会对现有的组合进行必要的调整，以确定一个新的最佳组合。( )

单词拼写。

1. The ship is sailing through the Panama C____.

2. The flood d____ a lot of houses and many people became homeless.

3. He was lucky enough to be r____ from drowning.

4. After e____ was cut off, the lights went out.

5. Trees along the road provide s____ from the sun for the farmers.

6. The bridge was badly d____ by the flood.

7. The boiling kettle was giving off s____.

8. The workers are d____ a well in the desert.

9. It's an h____ for me to be invited to speak here.

10. France lies in E____, neighbouring Germany.

某外商向国内一加工贸易企业提供价值港币1000元(当天外汇牌价的买卖中间价为100港币＝107元人民币)的塑料玩具样品，要求按样品加工生产。此批玩具样品进口时，海关应按( )办理放行手续。

A．保税

B．按人民币770元为完税价格征税

C．免税

D．按人民币1070元为完税价格征税

《工程建设项目勘察设计招标投标办法》中关于投标保证金的退还的说法，正确的是( )

A．招标人与中标人在采购合同签订后5个工作日内退还中标供应商的投标保证金
B．招标人与中标人签订合同后5个工作日内，应当向未中标的投标人退还投标保证金
C．招标采购单位应当在中标通知书发出后5个工作日内退还未中标供应商的投标保证金
D．招标人与中标人签订合同后5个工作日内，应当向中标人和未中标人一次性退还投标保证金

下列各项中（）属于狭义有价证券。

A.商业本票

B.可转换债券

C.运货单

D.借据