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How Many Trees Are There?
S4 E78 / 4m 15s
It may be an impossible questions, but we can at least get close.
Join Joe Hanson as he explores curiosity and illuminates the science behind… well, everything.
Video description: The flu might feel like some minor illness that you don’t need to worry about much, but tens of thousands of people still die from it every year. And back in 1918, Flu killed up to 5% of the world’s population. Could a flu that bad happen again?