Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Practical analysis of a dominant business practice

I was familiar with the 80/20 rule from my undergradate days at the University of Illinois and the author did a fine job of explaining with many examples. The rule that you get 80% of your gross receipts from 20% of your clients absolutely is true as confirmed from my CPA practice and from other businesses that I am familiar with. I highly recommend this practical book to all business people.