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物质的物理特征

> 下列说法中正确的是 A.一切物体都是温度升高时膨胀，温度降低时收缩 B.由于热胀冷缩，物体在温度升高时将略变轻些 C.生馒头在笼中蒸煮后发得很大，这主要不是因为受热膨胀引起的 D.铁路桥一端固定，另一端并不固定，这样在气温变化时铁桥可以自由伸缩

问题：

发布时间：2024-09-13

下列说法中正确的是

A.一切物体都是温度升高时膨胀，温度降低时收缩
B.由于热胀冷缩，物体在温度升高时将略变轻些
C.生馒头在笼中蒸煮后发得很大，这主要不是因为受热膨胀引起的
D.铁路桥一端固定，另一端并不固定，这样在气温变化时铁桥可以自由伸缩

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