Yes, it is.
Yes.
No, It's the metric unit for length
Kilometer is the largest unit in the metric system
There isn't a separate US metric system, the metric system is international and the same everywhere. So one kilometre in the U.S.A. is one kilometre.
kilometer
Yes, anything with 'meter' such as kilometer, meter, centimeter, decimeter, millimeter, etc. is a unit of measurement in the metric system.
The 'kilometer' is a unit of length or distance in the metric system.
Kilometer as regards to distance
A kilometer is one thousand meters(kilo means one thousand).
they all have to so with the metric system
The metric 'kilometer' is typically used to express the length of the same category of measurements as the English 'mile'. But it's a stretch to say that they are "about the same". One kilometer is almost 38% shorter than a mile.
The unit of length in the metric system is the meter (m); many derivatives are also used: kilometer, centimeter, micrometer, nanometer, etc.