448 students
From the first year of secondary school to postgraduate studies at universities around the world,...
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765 students
Aristotle as long ago as 350 B.C. began classifying living organisms on the Greek island...
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322 students
Huge bits of half-frozen steam floating in the sky. That’s probably the best non-technical description...
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126 students
Antonie van Leeuwenhoek lived for most of his long life (1632 to 1723) in the...
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362 students
In this lecture, we are looking at three stories – two of them very strange...
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692 students
A dummy test post for testing new mcq and written
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762 students
Throughout human history, one of the great questions has always been: where did we come...
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375 students
The first ‘people’ to walk on two legs probably stood up about four to five...
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196 students
What makes the sun a star and not a planet? Why does the earth have...
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150 students
Archimedes is one of the most famous mathematicians of all time and, perhaps, the first...
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