what do mules eat?

Feed the mules.

They are the offspring of female horses and male donkeys.

All events for horses are open to mules as well (and the mules usually win), but mules specifically are raced in Texas.

Mules cannot race in thoroughbred or quarterhorse races, and, they cannot out run either breed..Horses are faster than mules.

Two mules can be a brace of mules if they are paired, haltered and equipped to work. If there are more than two animals, they will normally be termed a team.