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Βι¶ΉΤΌΕΔ Two
Horizon
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Episodes
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Sleep Census
Information and Support
Main content
2009-2010
Horizon
Series exploring topical scientific issues
On iPlayer
Not available
Supporting Content
Jumping into a black hole
—
Who Is Afraid of a Big Black Hole?
Duration:
4:46
The problem of measuring coastlines
—
How Long is a Piece of String?
Duration:
6:23
Recording data on global population at the UN
—
How Many People Can Live on Planet Earth?
Duration:
4:44
How long is a piece of string?
—
How Long is a Piece of String?
Duration:
6:51
