Answer:
exchanges
Step-by-step explanation:
Marketing is the technique whose sole purpose is to increase the reach of product to the customers. It basically assures up to a certain level the sales revenue. Sales is basically the exchange of goods for money.
From goods the customers gets benefited and from the money the sellers or marketers gets benefited.
The main point is thus, the exchange of satisfaction in some form, from buyer to seller.
Marketing is thus the cure to the problem of customer reach and marketer income, through exchange between them.