Answer:
reading
The metre is currently defined as the length of the path traveled by light in a vacuum in 1299 792 458 of a second. The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole along a great circle, so the Earth's circumference is approximately 40000 km.
Math
The basic unit of length (or distance) in the Metric System. The symbol is m. For example: the length of this guitar is a little over 1 meter.
