ABC News Chief Medical Correspondent Dr. Jen Ashton said when returning to schools, we need to consider four elements.
"Density. How many students will that student be around?" she said, "How much time will students be in the room or in the school itself?"
Can schools hold classes outdoors or at least open windows?
"And how much space can be in between students? Some classrooms don't have the ability to space students out a minimum of six feet," Ashton said.
Ashton said, "It's a dynamic and rapidly-evolving situation so we'll have to take it day by day."
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