The author mentions food, tools and precious metals and stones together because they are all ________.

1.假冒伪劣商品是个严重问题。

2.一些原因导致了这种现象。

3.为了扫除假冒伪劣商品，……

Which of the following statements about computerized monetary systems is NOT supported by the passage?

According to the passage, coins once had real value as currency because they ______.

The author mentions food, tools and precious metals and stones together because they are all ________.

根据以下内容回答下列各题,

In ancient times wealth was measured and exchanged in things that could be touched: food, tools, and precious metals and stones. Then the barter system was replaced by coins, which still had real value since they were pieces of rare metal. Coins were followed by fiat money, paper notes that have value only because everyone agrees to accept them.

Today electronic monetary systems are gradually being introduced that will transform. money into even less tangible forms, reducing it to a series of “bits and bytes”, or units of computerized information, going between machines at the speed of light. Already, electronic fund transfer allows money to be instantly sent and received by different banks, companies, and countries through computers and telecommunications devices.

Which of the following would be the most appropriate title for the passage?

According to the passage, which of the following was the earliest kind of exchange of wealth?

The passage implies that buffalo chips were needed _______.

Which of the following does the author not express surprise at?

Whats the best title of the passage?

根据以下内容回答下列各题,

One of the greatest problems for those settlers in Nebraska in the last quarter of the previous century was fuel. Little of the state was forested when the first settlers arrived and it is probable that by 1880, only about one-third of the originally forested area remained, down to a mere 1 percent of the states 77,000 square miles. With wood and coal out of the question, and with fuel needed year-round for cooking, and during the harsh winter months for heating, some solution had to be foun

d． Somewhat improbably, the buffalo provided the answer. Buffalo chips (干粪块) were found to burn evenly, hotly, and cleanly, with little smoke and interestingly, no odor, Soon, collecting them became a way of life for the settlers children who would pick them up on their way to and from school, or take part in competitions designed to counteract their natural reluctance. Even a young man, seeking to impress the girl he wanted to marry, would arrive with a large bag of chips rather than with a box of candy or a bunch of flowers.

What is the main topic of this passage?