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根据下面资料，回答题 What are the zebra stripes on the tomato soup cans and potato chip bags? They are specialblack and white vertical lines. These black and white (21) can be read by an optical scanner, or computer. The "scanner," which (22) the lines of code, is a small laserbeam of light. When the light ray is broken by the black stripes, the computer "reads" the information about the product.
This code is (23) the Universal Product Code (UPC. It is designed (24) add speed and efficiency to stores by using computers. It can do this in (25) ways.
First, it is not necessary for workers to put individual prices on items. (26) using UPC, the computer can print out the accurate price of the item. Errors in prices are eliminated, or done(27) with. Also, the time spent checking out is reduced. (28) gives an itemized receipt To the customer (29) all the items, prices, and totals. The store clerk doesnot need to spend time checking the price on the item and punching it into the cash register. This
UPC computerized system will probably save as (30) as 45 percent of the checkout
clerk' s time.
What do the stripes mean? How does the computer interpret the stripes? The number (31) below the vertical bars identifies the manufacturer and the manufacturer' s item. As many as 10 trillion individual machine-readable numbers can be used with this system. In the example, the 0 onthe left side means that it is a grocery item. The (32) 51000 indicate the manufacturer.
In this case it is the Campbell Soup Company. The (33) five digits,00011, mean it is acan of tomato soup. The light rays from the light beam read these lines, and the message is sent directly to the computer. The computer (34) finds the information about this product(price, inventory data) and sends it instantly back to the terminal (35) the checkoutcounter. At the same time, it keeps an inventory for the store manager. Many products have labelswith these stripes.
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