First, you need to learn some basic terms. You probably know about position, distance and time. Use the link to watch a video lesson and find out what displacement, velocity and acceleration are.
A teacher of physics living in New York usually goes to his favourite Japanese grocery store on Saturday. His route is shown on the map and follows these steps:
follow the Hudson River upriver → cross the river using the George Washington Bridge → reverse direction and head downriver
Work out his actual displacement.
Displacement: ____ km