When did the three-field system start? - ANS-around 800 A.D.
How would a three-field system work? - ANS-split field into 3 parts; 2 of the fields were
used while the third rested for a year; switched every year
What did the three-field system do with food production? - ANS-increased food
production
What did the three-field system do for the population? - ANS-more people were
well-fed; they lived longer; Europe's population increased