There is only one biosphere. The biosphere is the culmination of all life on Earth, hence, sphere.
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If you asking where you'd find them in the real world - Binoculars and telescopes are two examples.
Two gears turning each other .
When two angles have common vertex and side but do not overlap, they are said to be adjacent angles. Some real examples are intersection of two roads, hands of a clock etc.
A real life example would be the two angles on the sides of the Leaning Tower of Pisa.
by throwing a coins or dice? maybe...