Q1 - At the heart of understanding marketing is something known as the marketing concept. In essence the marketing concept states:

focus on creating transactions
understand customer wants and needs
focus on market innovations
understand consumer levels of involvement with purchase decisions
Q2- At this point in your study of business you already know about the 80/20 rule. Yet, we now have the 80/20/30 rule. Thus, what does the "30" in the 80/20/30 rule indicate?

30% of customers account for 80% of profits
30% of the 20% of most profitable customers are up for grabs at any one point in time
30% of a firm's operating costs can be attributed to satisfying the top 20%
30% of customers are dissatisfied customers which little can be done about
50% of profits are lost serving the bottom 30% of customers