TASK DEFINITION: Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.
PROBLEM: Context: From a human point of view, natural resources can be classified as either renewable or nonrenewable. Renewable resources are natural resources that are remade by natural processes as quickly as people use them. Examples of renewable resources include sunlight and wind. They are in no danger of being used up. Metals and some other minerals are considered renewable as well because they are not destroyed when they are used. Instead, they can be recycled and used over and over again. Living things are also renewable resources. They can reproduce to replace themselves. However, living things can be over-used or misused to the point of extinction. For example, over-fishing has caused some of the best fishing spots in the ocean to be nearly depleted, threatening entire fish species with extinction. To be truly renewable, living things must be used wisely. They must be used in a way that meets the needs of the present generation but also preserves them for future generations. Using resources in this way is called sustainable use. Nonrenewable resources are natural resources that cant be remade or else take too long to remake to keep up with human use. Examples of nonrenewable resources are coal, oil, and natural gas, all of which are fossil fuels. Fossil fuels form from the remains of plants and animals over hundreds of millions of years. We are using them up far faster than they can be replaced. At current rates of use, oil and natural gas will be used up in just a few decades, and coal will be used up in a couple of centuries. Uranium is another nonrenewable resource. It is used to produce nuclear power. Uranium is a naturally occurring chemical element that cant be remade. It will run out sooner or later if nuclear energy continues to be used. Soil is a very important natural resource. Plants need soil to grow, and plants are the basis of terrestrial ecosystems. Theoretically, soil can be remade. However, it takes millions of years for soil to form, so from a human point of view, it is a nonrenewable resource. Soil can be misused and eroded (see Figure 25.9). It must be used wisely to preserve it for the future. This means taking steps to avoid soil erosion and contamination of soil by toxins such as oil spills. Some of the resources we depend on the most are energy resources. Whether its powering our lights and computers, heating our homes, or providing energy for cars and other vehicles, its hard to imagine what our lives would be like without a constant supply of energy. Fossil fuels and nuclear energy are nonrenewable energy resources. People worldwide depend far more on these energy sources than any others. Figure 25.10 shows the worldwide consumption of energy sources by type in 2010. Nonrenewable energy sources accounted for 83 percent of the total energy used. Fossil fuels and the uranium needed for nuclear power will soon be used up if we continue to consume them at these rates. Using fossil fuels and nuclear energy creates other problems as well. The burning of fossil fuels releases carbon dioxide into the atmosphere. This is one of the major greenhouse gases causing global climate change. Nuclear power creates another set of problems, including the disposal of radioactive waste. Switching to renewable energy sources solves many of the problems associated with nonrenewable energy. While it may be expensive to develop renewable energy sources, they are clearly the way of the future. Figure 25.11 represents three different renewable energy sources: solar, wind, and biomass energy. The three types are described below. You can watch Bill Nyes introduction to renewable energy resources in this video: MEDIA Click image to the left or use the URL below. URL: Solar energy is energy provided by sunlight. Solar cells can turn sunlight into electricity. The energy in sunlight is virtually limitless and free and creates no pollution to use. Wind energy is energy provided by the blowing wind. Wind turbines, like those in Figure 25.11, can turn wind energy into electricity. The wind blows because of differences in heating of Earths atmosphere by the sun. There will never be a shortage of wind. Biomass energy is energy provided by burning 
 Question: If natural gas continues to be used at current rates, it will be used up in a few

SOLUTION: decades.

PROBLEM: Context: Modeled after US hot website.com, group buying websites are now popular in China. These websites use the power of group buying to get competitive discounts for a daily deal on some best stuff to do, see, eat and buy in the cities across China. Discounts are available within just one click. Zhao lei, a software engineer in Beijing, loves the one-hour lunch break at noon,as it is the best time for him to check "today's special" at his favorite group buying websites . Sometimes he searches for great deals at directory sites devoted to the new shopping space. Zhao spends around 800 yuan($117.65) on group buying every month, mostly to buy food coupons for eating at some nice restaurants and occasionally to find something fun to do. " I love group buying. In addition to the competitive discounts it offers, it helps me get something fun, exciting and new, and such surprises give me a reason to try something new," he said. When he finds a really good bargain, he will send the link to friends or colleagues through MSN,QQ, or e-mail, or share the information at some social networking websites. In doing so, he often gets a certain cut off the price. At some sites, buyers are invited to leave notes about what they want to buy and the website will consider it if similar applications reach a certain number. That is how Zuo got her digital camera after waiting for two months. "It is cool. I want to buy a new digitgal camera for my trip to Switzerland this winter, but I never expected such cheap prices!" Zuo said. 
 Question: What is the passage mainly about?

SOLUTION: group buying

PROBLEM: Context: In 1989, Z Channel faded to black and was replaced by SportsChannel Los Angeles. 
 Question: Which replaced the Z Channel?

SOLUTION:
sportschannel los angeles