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(Source: "California Covid-19 Response Kit" )
Video: Graphic modeling of how micro-droplets carrying Covid-19 virus can remain in the air for some time. (Source: NHK-World Japan.)
Videos: "COVID-19: It Could Happen to Anyone: The Risk Is Real". Survivors tell their stories. (Source: County of Los Angeles)
(Source: "Frequently Asked Questions about Cloth Face Coverings" by City of Santa Monica. Contagion defined.)