A unit of measurement within the metric system, by the British, that caused the French Revolution, and eventually spread across the world, due to its use of increments of ten, making it easier to use ,to all countries except for three. One of these countries was called βThe United States of Americaβ, the reason for this is because by the time the metric system had spread, the United States had already gained their independence, and made the U.S. Primary system. As for a kilometer, it is the largest length measurement, consisting of 10 dekameters, 100 meters, 1,000 decimeters, and 10,000 centimeters. Hope that answers your question.
- QSD_M
P.S. I am from America and the primary system is stupid.