01 / 9Practical Engineering≈ approximate level B17:30–7:33 .
02 / 9Practical Engineering≈ approximate level B25:56–6:02
- .
03 / 9Practical Engineering≈ approximate level C18:44–8:52
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04 / 9Practical Engineering≈ approximate level C17:27–7:34
, , ’s .
05 / 9WIRED≈ approximate level C12:41–2:47
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06 / 9TED≈ approximate level C19:10–9:19
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07 / 9Practical Engineering≈ approximate level C10:00–0:12
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08 / 9SciShow≈ approximate level C19:38–9:47
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09 / 9Big Think≈ approximate level C13:42–3:59
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