The Fastest Racehorse

Classical Mechanics Level 1

The Kentucky Derby is the most important horse race in America, and is also known for the amazing hats people wear for the race. The race itself is $2~\mbox{km}$ long and the winning horse this year was Orb in a time of $2~\mbox{minutes}$ , $2.89~\mbox{seconds}$ . What was Orb's average speed in m/s?