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Most scientists conclude that it is the increasing global temperature that leads to the increasing levels of carbon dioxide in the Earth's atmosphere. This may be due to the different chemicals that are being emitted in the air. Hope this helps.
Answer: Time zones created a standard of time that all trains followed
It was "A. Pythagoras" who was the Greek mathematician who systematized geometry and wrote a textbook that organized all the existing information about geometry, although many other Greeks were well-versed in this subject.
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The Harappan civilization was located in the Indus River valley. Its two large cities, Harappa and Mohenjo-daro, were located in present-day Pakistan's Punjab and Sindh provinces, respectively. Its extent reached as far south as the Gulf of Khambhat and as far east as the Yamuna (Jumna) River.
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