Answer:
Both transactions, the one at the University ticket window as well as the sale at the concert entrance, occurred in markets.
Explanation:
A market is a set of suppliers and demanders whose tradings establishes the price of a good or service. In this pace or point, buyers and sellers negotiate for exchange of well defined products or services.
Market is said to exist wherever there is a potential for trade.
Is the accumulation of buyers and sellers where competition between buying and selling is estalished.
In this case, the first situation is the buying of the tickets at the University. First trade.
The second situation, is the selling of the third ticket in the outside of the entrance. Second trade.