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A．3 bags.B．10 bags.C．they don't have any bags.D．5 bags.
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听力原文：W: Will I have to wait long for a bus？
M: Not at all! The 333 comes past there all the time. It's a very busy area.
Q: How long will the woman have to wait？
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A．Projected changes in the building code.B．Design features of modem skyscrapers.C．Stra
Mobile phones
What Are Mobile Phones？
A mobile phone, also known as a cellphone or cellular phone, is a portable electronic device which behaves as a normal telephone whilst being able to move over a wide area (compare cordless phone which acts as a telephone only within a limited range). Cellphones allow connections to be made to the telephone network, normally by directly dialing the other party's number on an inbuilt keypad. Most current cellphones use a combination of radio wave transmission and conventional telephone circuit switching, though packet switching is already in use for some parts of the cellphone network, especially for services such as Internet access and WAP.
Some of the world's largest cellphone manufacturers include Alcatel, Audiovox, Kyocera (formerly the handset division of Qualcomm), LG, Motorola, Nokia, Panasonic (Matsushita Electric), Philips, Sagem, Samsung, Sanyo, Siemens, SK Teletech, and Sony Ericsson.
There are also specialist communication systems related to, but distinct from cellphones, such as satellite phones and Professional Mobile Radio.
Worldwide Deployment
Cellphones have a long arid varied history that stretches back to the 1950s, with hand held devices being available since 1983. Due to their low establishment costs and rapid deployment, cellphone networks have since spread rapidly throughout the world, outstrip ping the growth of fixed telephony.
In most of Europe, wealthier parts of Asia, Australia, and the US, cellphones are now widely used, with the majority of the adult, teenage, and even child population owning one. The number of cell phone subscribers in the US has reached over 190 million. The availability of Prepaid or pay as you go services, where the subscriber does not have to commit to a long term contract, has helped fuel this growth.
Standardized Technology
The cellphone has become ubiquitous because of the interoperability of cellphones across different networks 4nd countries. This is due to the equipment manufacturers all working to the same standard, particularly the GSM standard which was designed for Europe-wide interoperability. All European nations and some Asian nations chose it as their sole standard, while in Japan and South Korea another standard, CDMA, was select ed.
Cellphone Culture
In less than twenty years, mobile phones have gone from being rare and expensive pieces of equipment used by businesses to a pervasive low-cost personal item. In many countries, cellphones now outnumber land line telephones, with most adults and many children now owning cellphones. It is not uncommon for young adults to simply own a cell phone instead of a land-line for their residence. In some developing countries, where there is little existing fixed-line infrastructure, the mobile phone has become widespread.
Social Life
With high levels of mobile telephone penetration, a mobile culture has evolved, where the phone becomes a key social tool, and people rely on their cellphone addressbook to keep in touch with their friends. Many people keep in touch using SMS, and a whole culture of "texting" has developed from this. The commercial market in SMS's is growing. Many phones even offer Instant Messenger services to increase the simplicity and ease of texting on phones.
Entertainment
The mobile phone itself has also become a totemic and fashion object, with users deco rating, customizing, and accessorizing their cellphones to reflect their personality. Like wise, customized ringtones have been developed.
Etiquette
Cellphone etiquette has become an important issue with mobiles ringing at funerals, weddings, movies and plays. Users often speak at increased volume, with little regard for others nearby people. It has become common practice for places like libraries and movie theatres to ban the use of cell phone
受托机构应与信用评级机构就资产支持证券跟踪评级的有关安排作出约定，并应于资产支持证券存续期内每年的()前向投资者披露上年度的跟踪评级报告。
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