While a constant supply of freshwater happens by itself in natural streams, an aquarium is by definition, a closed system. So here, man has to help out in order to provide new..
It is about 4.22 light-years<span> from Earth and is the closest star other than the sun. Alpha Centauri A and B orbit a common center of gravity every 80 years. The average distance between them is </span>about 11 astronomical units<span> (AU) — about the same distance as the sun is to Uranus.</span>
The answer is carbohydrate.
