In The Decision Book: 50 Models for Strategic Thinking, refer to "The Pareto Principle." According to the authors, economist Vilfredo Pareto observed what? Question 12 options: 80% of Italy's wealth at the time belonged to 20% of the population. 60% of Italy's wealth at the time belonged to 40% of the population. 70% of Italy's wealth at the time belonged to 30% of the population