01 / 15PBS NewsHour≈ approximate level B10:36–0:46 , .
02 / 15Big Think≈ approximate level A20:04–0:09
, , - .
03 / 15CNBC Make It≈ approximate level B23:09–3:16
.
04 / 15Big Think≈ approximate level B12:59–3:06
.
05 / 15BBC Earth≈ approximate level B11:01–1:07
.
06 / 15CNBC Make It≈ approximate level B19:27–9:33
, .
07 / 15WIRED≈ approximate level B10:14–0:19
, , .
08 / 15PBS NewsHour≈ approximate level B10:11–0:17
.
09 / 15TED-Ed≈ approximate level B10:06–0:11
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10 / 15CNBC Make It≈ approximate level C15:28–5:34
.
11 / 15PBS NewsHour≈ approximate level C11:04–1:12
-- -- , -.
12 / 15The School of Life≈ approximate level B22:40–2:50
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13 / 15WIRED≈ approximate level B16:28–6:39
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14 / 15The School of Life≈ approximate level C12:24–2:37
; - .
15 / 15NBC News≈ approximate level C10:22–0:32
.