Pleasse help me ! About length ..

If you want to measure something on a map, you may use a program called 'Google Earth', in there you can see every corners in the world. In the program tool bar, you may select 'Ruler' to measure distance. If you want to measure it in kilometre, make sure you change it in 'Option' of 'Ruler'. At last, you may download the program or have more information about 'Google Earth' by going to following Link.

Website Link: http://earth.google.com

I hope i can help you

Extra Information:
1km=:
1000m
100000cm
1000000mm