阅读理解。
One hundred and thirteen million Americans have at least one bank-issued credit card. They give
their owners automatic credit in stores, restaurants, and hotels, at home, across the country, and
even abroad, and they make many banking services available as well. More and more of these credit
cards can be read automatically, making it possible to withdraw or deposit money in scattered locations,
whether or not the local branch bank is open. For many of us the "cashless society" is not on the
horizon----it's already here.
While computers offer these conveniences to consumers, they have many advantages for sellers too.
Electronic cash registers can do much more than simply ring up sales. They can keep a wide range of
records, including who sold what, when, and to whom. This information allows businessmen to keep
track of their list of goods by showing which items are being sold and how fast they are moving.
Decisions to reorder or return goods to suppliers can then be made. At the same time these computers
record which hours are busiest and which employees are the most efficient, allowing personnel and
staffing assignments to be made accordingly. And they also identify preferred customer for promotional
campaigns. Computers are relied on by manufacturers for similar reasons. Computer analyzed marketing reports can help to decide which products to emphasize now, which to develop for the future and which
to drop. Computers keep track of goods in stock, of raw materials on hand, and even of the product
ion
process itself.
Numerous other commercial enterprises, from theaters to magazine publishers, from gas and electric
utilities to milk processors, bring better and more efficient services to consumers through the use of
computers.
1．According to the passage, the credit card enables its owner to .
A. withdraw as much money from the bank as he wishes
B. obtain more convenient services than other people do
C. enjoy greater trust from the storekeeper
D. cash money where he wishes to
2．From the last sentence of the first paragraph we learn that .
A. in the future all the Americans will use credit cards
B. credit cards are mainly used in the United States today
C. nowadays many Americans do not pay in cash
D. it is now more convenient to use credit cards than before
3．The phrase "ring up sales" most probably means .
A. make an order of goods
B. record sales on a cash register
C. call the sales manager
D. keep track of the goods in stock
4．It can be inferred that .
A. computers will bring disaster
B. computer industry will not develop faster
C. computers will bring about more convenience to people's life
D. None
xC（g）+ 2D（g）△H<0。2min末该反应达到平衡，生成0.8mol D ，并测得C的浓度为0.2mol·L－1。请填空：