215,628 people
200 people
32people participated i
550 athletes participated in the first commonwealth games
67 countries first participated in the International Geophysical Year in 1957-1958.
Enough
about 201026541651 people
8 teams participated in th opening world cup 1975
According to the Wikipedia article on Earth Day (related link below) approximately 20,000,000 Americans participated in the first Earth Day.
1600
13
52
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