A cashier gives one person a five dollar bill and 15 one dollar bills in exchange for a $20 bill. He gives a second person a $10 bill a five dollar bill and 51 dollar bills in exchange for a $20 bill. What characteristic of money does this illustrate?

Divisibility uniformity durability portability

This situation illustrates the characteristic of divisibility of money. The cashier is able to give different combinations of bills (in this case, denominations of $1, $5, and $10) to make up the desired amount. This shows that money can easily be divided into smaller units to make transactions easier.