The world’s richest tennis player, Martina Navratilova, became the first to make $10 million.
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The first International Women's Day was celebrated.
The hashtag #5secondsofsummer trended worldwide for the first time on Twitter.
The Zodiac Killer shot his first victim Mario Orosco.
Philips demonstrated the compact disc publicly for the first time.
The first official rock festival took place in the Soviet Union.
