Marsupials are found in north america and australia, but they would not have been able to swim across the ocean. according to scientists, how did this group of organisms come to live on two separate continents?

Because liquids flow freely, they take the shape of the container they are in, but have a definite volume. Like liquids, the shape of a gas changes with the container. This is because the atoms in a gas move rapidly and freely to fill any available space. Unlike liquids, the volume of a gas changes depending on the container it is in.

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