HEEELLPP I DON'T UNDERSTAND

Question

An ant is crawling on your ruler. He is on the 6 cm. mark and he crawls back to the 2 cm mark. He does this in 2 seconds. What is the distance he crawls? What is his speed? What is his velocity? 

(Sorry i added this twice)

Answer 1

If the ant starts on the 6 cm mark and crawls back to to the 2 cm mark it has moved 4 cm (6-2) in the negative direction.

Its distance is 4 cm. (The ant's displacement is -4 cm).

the ant's speed: r=d/t Rate (Speed) = 4/2 = 2 cm/sec.

Velocity is a vector quantity which means that it has quantity and direction. So the ant's velocity is 2cm/sec in the negative direction.