47 -From the passage, we understand that the term "homo sapiens” is ---- .
A) a method of analysing fossils
B) a way of referring to a large number of species of flora and fauna
C) another term for the human race
D) an irreplaceable ecosystem which is being destroyed
E) a hostile environment in which many species die
48 -The author predicts that ---- .
A) there will be no harmful effects from so many species dying
B) the world might be turned upside down by colliding with an asteroid
C) mankind will find a solution to the problem
D) more species may die out this time than ever before
E) the human population will soon reach six billion
Rays of sunlight travel from 150 million kilometres away, and when they reach the Earth, they
are parallel rays. The curve of the Earth means that the rays are vertical at the Equator but at quite
a low angle when they reach temperate latitudes. As the rays lose heat passing through the
atmosphere, the more direct the journey, the greater the heat which penetrates through to the
surface of the Earth. The vertical rays in equatorial latitudes mean that it is much hotter at the
Equator than it is in the regions where the sun's rays strike at a low angle. It is these variations in
temperature that are largely responsible for the changes in weather.
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