The early Moon developed as a mostly liquid ball of magma covered with a thin crust of lighter minerals.

早期的月球大部分是熔浆构成的液体装球体，表面覆盖着一层较轻矿物组成的薄壳。

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Aluminum foil as glassware scrubber: To get baked-on food off a glass pan or an oven rack, use dishwashing liquid and a ball of foil in place of a steel-wool soap pad, says Mary Findley, president of the cleaning-products developer Mary Moppins.

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He then tested how much friction there was when a ceramic ball and a polyethylene socket were immersed in a liquid with the same properties as synovial fluid.

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