Sound waves travel around the boxed room causing them to bounce off the nearest walls to the end of the room
El helio es más ligero que el aire y a diferencia del hidrógeno no es inflamable, siendo además su poder ascensional un 8 % menor que el de este, por lo que se emplea como gas de relleno en globos y zepelines publicitarios, de investigación atmosférica e incluso para realizar reconocimientos militares.espero ke esto ayude!
Mass extinction occur from natural disasters, such as a n asteroid hitting earth or a volcano errupting and spread ash everywhere.
It makes sense to measure geologic time between mass extinctions because after each mass extinction, there is almost no life left and the few left have to repopulate, which may lead way to new mutations and new varieties of plants and animals.
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Answer:
D
Explanation:
F = G m1 m2 / r^2 now double r
F = G m1m1/ (2r)^2
F = 1/4 G m1m2/r^2 <===== this is 1/4 of the original
