Answer:
"It brought the Allies closer together." and "It convinced many Europeans that Soviet expansion posed a real threat."
this would take me a while to figure out, so i will just help you with a website. this should help you.
https://www.census.gov/data/tables/2008/demo/voting-and-registration/p20-562-rv.html
goodluck :)
I can list a couple for both I guess.
Opening:
People getting infected, angry parents, school administration being flamed and you can be fired potentially, a negative thing from my perspective.
Closing:
Very low risk for students being infected, work from home, more time for students to rest, meaning a overall positive thing in my opinion.