On this day, April 1, in 1901, Emilio Aguinaldo took an oath of allegiance to the US government.
The official calendar of the Republic of the Philippines: an almanac of Philippine commemorations enlivened with illustrations and information. –Manila: Presidential Communications Development and Strategic Planning Office, [20
14].
On this day, in 1976 Steve Jobs, Steve Wozniak, and Ronald Wayne founded Apple Computer Inc.
https://www.britannica.com/on-this-day/April-1
On this day in 1960, the US launched the first weather observation satellite, Tiros I.
https://todayinsci.com/4/4_01.htm
April is the Month of Planet Earth (Proclamation No. 1482, s. 2008)
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