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http://www.pbs.org/wgbh/buildingbig/lab/images/forces_off.gif | 20:51:51 Jan 5, 2021
Got an HTTP 302 response at crawl time
Redirecting to...
https://www-tc.pbs.org/wgbh/buildingbig/lab/images/forces_off.gif
Impatient?
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