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e distance away from them. most of their bulk is hidden below the water, so their underwater parts may extend out far beyond the visible top. also, they may roll over unexpectedly, churning the waters around them. icebergs are parts of glaciers that break off, drift into the water, float about awhile, and finally melt. icebergs afloat today are made of snowflakes that have fallen over long ages of time. they emb