(d) option is right answer
The distance is measured between the 'centers of mass',
or 'centers of gravity' of both objects. That's the point inside
the object where there's the same amount of mass in every
direction away from it.
If the object is something like a sphere, or a cube, or a uniform
wooden board, or anything "symmetrical", then the center of mass /
center of gravity is the actual center of the object. If the object has
some irregular shape, then it's harder to calculate or measure where
its center is.
Answer:
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Answer:
Los movimientos verticales o circulación convectiva consisten en un intercambio de lugar entre el aire caliente de las capas bajas y el aire frío de las superiores. Este movimiento se debe a la diferencia de densidades de las distintas masas de aire. Los movimientos horizontales se basan en las diferencias de presión.