In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.
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Question: Article: Group buying is one of the fastest growing trends in South Africa today. Industry leaders are confident the growth potential remains strong since group buying is location-specific. Start-up costs are low and profit room remains high, so many sites continue to receive invested money despite widespread criticism and Facebook's decision to _ deal business due to privacy concerns. In the early stages of all industries, some companied fail because they cannot compete with stronger companies in difficult economic conditions. To deal with difficult conditions, an alarming number of businesses are developing group buying websites in places like China and India, so the increase of group buying in South Africa is nothing more than a natural progression into the international mainstream. The group buying concept is fairly new and consumers have accepted this concept because they can now make full use of the rich information available on the Internet. Group buying is convenient and easy so it works. Anyone can view a site, join a mailing list, subscribe to RSS or print out a coupon . The current group buying structure offered by the industry leaders works although there are still challenges to overcome. Perhaps, the future of group buying is tied to the joining together of social media and mobile devices. Mobile devices are with us wherever we go and almost everyone is using some type of social media site like Facebook or Twitter to stay informed. Using GPS and social media technology to provide real time location-specific promotions would be beneficial to every consumer looking for the best deals in town. Pause for a moment and think about it! What is better than signing on to your phone while having fun in town and you receive a real time information that your favorite shop across the street is offering a killer dial? The future of the group buying in South Africa is bright and we can expect to see more advanced approaches to this concept in the future. In addition to the technological advances consumers will see the range of promotions expand to include new products and services.
Answer: group buying is an international trend

Answer: The author sets China and India as examples to show that _ .

Question: Article: Sudan is a rather large nation in the northeastern part of Africa. It has about twenty million people. It also has a short coastline along the Red Sea. Some northern areas of the country have deserts while the southern part has tropical rain forest. Their capital city is Khartoum. At Khartoum the Blue Nile and the White Nile come together to form the Nile River, which is the world's longest river. Khartoum has about four hundred and seventy thousand people. There are two groups of people who live in Sudan. In the northern part of the country, there are many Arabic-speaking Muslims. They make up about two-thirds of the total population. In the southern area, there are groups of people who speak African languages. The northern and southern areas also have different histories. People in the south lived by themselves for many years. However, the northern area was controlled by foreigners for several centuries. After the World War II, Sudan became completely independent.
Answer: 2%

Answer: People living in the capital city of Sudan make up more than _ of the total population.

Question: Article: We all enjoy the colors of autumn leaves. Did you ever wonder how and why a fall leaf changes color? Where do the yellows and oranges come from? To answer those questions, we first have to understand what leaves are and what they do. Leaves are nature's food factories. Plants take water from the ground through their roots. They take a gas called carbon dioxide from the air. Plants use sunlight to turn water and carbon dioxide into glucose, which is a kind of sugar. Plants use glucose as food for energy and as a building block for growing. The way plants turn water and carbon dioxide into sugar is called photosynthesis, which means " putting together with light. " A chemical called chlorophyll helps make photosynthesis happen. Chlorophyll is what gives plants their green color. As summer ends and autumn comes, the days get shorter and shorter. This is how the trees "know" to begin getting ready for winter. During winter, there is not enough light or water for photosynthesis. The trees will rest, and live off the food they stored during summer. They begin to shut down their food-making factories. The green chlorophyll disappears from the leaves. As the bright green fades away, we begin to see yellow and orange colors. Small a-mounts of these colors have been in the leaves all along. Covered up by the green chlorophyll, we just can't see them in summer. The bright reds and purples we see in leaves are made mostly in the fall. In some trees, like maples, glucose is trapped in the leaves after photosynthesis stops. Sunlight and the cool nights of autumn cause the leaves turn this glucose into a red color. The brown color of trees like oaks is made from wastes left in the leaves. It is the combination of all these things that make the beautiful colors we enjoy in the fall.
Answer: introduce the topic of the passage

Answer:
The writer asked two questions in the beginning in order to_.