The staggering variety of free stuff available on the Internet sometimes seems to have repealed the first law of economics: There"s no such thing as a free lunch . But as so often happens, the dismal science actually has it right. When it looks like you"re getting something for nothing, somebody is paying, and it"s often instructive to know who that is. I"ve been testing a new phone service called ooma that provides an interesting case in point. Once you pay $399 up front for a box called the ooma Hub and connect it to your phone and the Internet via your home network, you are promised free, unlimited phone calls over two lines, plus voice mail. The system works fine and is simple to set up. When a voice-over-Internet call has to go to a regular phone number, a service such as ooma usually has to pay a "temination fee" to a carrier such as Verizon. Skype, for example, charges 2% per minute for calls outside the Skype network. But ooma avoids this by using some of its customers—those who have kept regular phone lines—to serve as gateways onto the local phone network at no charge. When you want to call outside the ooma network, the call moves from your Hub over the Internet to a second landline-connected Hub within the destination"s local calling area The Hub dials the target number and patches the call through. In effect, ooma customers with landlines pay to keep the whole system going. You don"t even notice if your landline is being used because your own phone calls go out over your broadband connection, with your flat-rate monthly phone bill covering the ooma traffic. In fact, this improves the efficiency of the phone system by putting idle lines to work. But if ooma ever gains real traction, I expect a legal assault from big phone companies, which are losing income from termination fees. Web services do take advantage of genuine economies. The phone network is more expensive than the Net. Lots of Net players build on these advantages. Skype relies on selected users who act, often without their knowledge, as "super nodes" to manage the system. FreeConference.com provides calls by taking advantage of regulatory quirks—namely, the stiff termination fees long-distance carriers must pay to certain rural phone companies that handle calls into their territory. In effect, the free conferences are subsidized by customers and shareholders of the long-distance carriers. You may as well enjoy free calls while you can. But it"s always a good idea to read the fine print. If it isn"t obvious who"s paying for a free service, it might well be you.
单选题 The phrase "a free lunch"(Line 3, Paragraph 1)implies that the free stuff on the Internet seems to be
【正确答案】 B
【答案解析】解析:短语语义理解题。根据a free lunch定位到文章首段第一句。第三句提到看似免费的服务实质上总得有人买单,故选B。
单选题 The ooma system promised free, unlimited phone calls by
【正确答案】 B
【答案解析】解析:推理判断题。文章第三段提到ooma是通过利用一些使用常规电话线的用户而提供免费无限制打电话的服务,故选B。
单选题 It could be concluded from the passage that the ooma service
【正确答案】 B
【答案解析】解析:推理判断题。文章第四段倒数第二句提到ooma利用了闲置的电话线路,提高了电话系统的使用效率,故选B。
单选题 One cannot notice if the landline is being used by others because
【正确答案】 B
【答案解析】解析:推理判断题。第四段第四句指出人们不会注意到电话费的变化,因为每月的电话费几乎都是固定的,故选B。
单选题 The author suggests that readers
【正确答案】 C
【答案解析】解析:主旨大意题。文章结尾_处指出用户有必要弄清楚谁在为所谓的免费服务买单,否则很有可能是他们自己。因此作者实际上是在建议读者一定要留意自己的账单,C项正确。