Genesis 7:20

20The waters prevailed above the mountains, covering them fifteen cubits
A  cubit was about 18 inches or 45 centimeters
deep.

Deuteronomy 3:11

11(For bonly Og the king of Bashan was left of the remnant of cthe Rephaim. Behold, his bed was a bed of iron. Is it not in dRabbah of the Ammonites? Nine cubits
A  cubit was about 18 inches or 45 centimeters
was its length, and four cubits its breadth, according to the fcommon cubit.
Hebrew cubit of a man
)

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