01 / 13Practical Engineering≈ approximate level A22:06–2:12 .
02 / 13TED-Ed≈ approximate level B21:21–1:29
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03 / 13Practical Engineering≈ approximate level C18:24–8:31
, .
04 / 13Practical Engineering≈ approximate level B110:28–10:33
.
05 / 13Practical Engineering≈ approximate level B29:38–9:47
, .
06 / 13Practical Engineering≈ approximate level B12:38–2:42
, .
07 / 13Practical Engineering≈ approximate level C17:53–8:00
, .
08 / 13CrashCourse≈ approximate level C17:23–7:33
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09 / 13Practical Engineering≈ approximate level B22:31–2:35
, .
10 / 13Mark Rober≈ approximate level B24:13–4:17
, - .
11 / 13TED≈ approximate level C18:00–8:10
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12 / 13Mark Rober≈ approximate level B20:40–0:44
, .
13 / 13Practical Engineering≈ approximate level C12:47–2:58
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