You can't measure an area in kilometers. It's square kilometers.
123
1800
6.25 miles
988 kilomiters.
9,600 kilomiters and 8,000 miles
104.6 km/h
6,000 miles is about 9656km
4 kilomiters. 4 or 5 hours to get there
So far as i know, the abbreviation for Kilometers is km.
12,349 kilometers is 7,673.3 miles.
4 km = 400,000 cm
Spain is in Europe.