Please answer this: Extract the answer to the question from the following context. Question: Why do people breed plants? Context: Virtually all staple foods come either directly from primary production by plants, or indirectly from animals that eat them. Plants and other photosynthetic organisms are at the base of most food chains because they use the energy from the sun and nutrients from the soil and atmosphere, converting them into a form that can be used by animals. This is what ecologists call the first trophic level. The modern forms of the major staple foods, such as maize, rice, wheat and other cereal grasses, pulses, bananas and plantains, as well as flax and cotton grown for their fibres, are the outcome of prehistoric selection over thousands of years from among wild ancestral plants with the most desirable characteristics. Botanists study how plants produce food and how to increase yields, for example through plant breeding, making their work important to mankind's ability to feed the world and provide food security for future generations. Botanists also study weeds, which are a considerable problem in agriculture, and the biology and control of plant pathogens in agriculture and natural ecosystems. Ethnobotany is the study of the relationships between plants and people. When applied to the investigation of historical plant–people relationships ethnobotany may be referred to as archaeobotany or palaeoethnobotany.
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Answer: increase yields


Please answer this: Extract the answer to the question from the following context. Question: Where is Melbourne Airport? Context: The main passenger airport serving the metropolis and the state is Melbourne Airport (also called Tullamarine Airport), which is the second busiest in Australia, and the Port of Melbourne is Australia's busiest seaport for containerised and general cargo. Melbourne has an extensive transport network. The main metropolitan train terminus is Flinders Street Station, and the main regional train and coach terminus is Southern Cross Station. Melbourne is also home to Australia's most extensive freeway network and has the world's largest urban tram network.
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Answer: Australia


Please answer this: Extract the answer to the question from the following context. Question: Various early things are what kind of content? Context: Much of the material in the Canon is not specifically "Theravadin", but is instead the collection of teachings that this school preserved from the early, non-sectarian body of teachings. According to Peter Harvey, it contains material at odds with later Theravadin orthodoxy. He states: "The Theravadins, then, may have added texts to the Canon for some time, but they do not appear to have tampered with what they already had from an earlier period."
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Answer:
teachings