What does a x in the gradebook mean

X is excused, usually used in extra credit assignments you don't do or when you have been absent from school and not have been able to turn in an assignment.

for the points : )

explanation:

the right answer is the end of world war ii

after the end of a global wwii all the nations involved, in an attempt to create an organization to maintain world peace. this agreement would work settling international disputes via negotiation and arbitration instead of leading the issues escalate to another war.