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<title>Challenge: Famous discoveries</title>
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<h1>Famous discoveries</h1>
<h2 id="math-heading">Math discoveries</h2>
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<li>323–283 BC – Euclid: wrote a series of 13 books on geometry called The Elements</li>
<li>Al-Khawarizmi (780-850): wrote the first major treatise on Algebra titled "Al-jabr wal-muqabaleh"</li>
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<h2 id="science-heading">Science discoveries</h2>
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<li>1543 – Copernicus: discovered the heliocentric model of the solar system.
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<li>1672 – Sir Isaac Newton: discovers that white light is a spectrum of a mixture of distinct coloured rays.</li>
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<a href="https://en.wikipedia.org/wiki/Timeline_of_scientific_discoveries">Read about more discoveries on Wikipedia.</a>
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var math = $("#math-heading");
math.text(math.text() + "!! WOW!");
var science = $("#science-heading");
science.text(science.text() + " Walla!")
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