Bones are living tissue which have their own blood vessels and are made of various cells, proteins, minerals and vitamins. This structure enables them to grow, transform and repair themselves throughout life.During childhood and adolescence, cartilage grows and is slowly replaced by hard bone.That is why children bones are a little harder to break but adult bone a little easier to break because there bone gets harder when they grow :)
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Answer:
They are examples of erosion by water in different forms
Explanation:
