Light year is used to measure the stellar distances whereas miles and km is used to measure distance on Earth.
Miles.
Miles
Because of the unwieldy large numbers that would otherwise be required.A Parsec is the distance from the Sun to Earth, and a light year is the distance that light would travel in a year.
Astronomical Unit (AU).
To measure the distance of stars you have to measure by light years.
metres
Light Years.
Litres. (L)
Measuring Lake Erie from the Canadian side would probably be in kilometers. On the US side would probably be in miles.
AnswerMiles, and that distance is about 480.8 miles
Feet
Kilometres or miles.