How many millimiters are in one liter?

Answer 1

NONE ;-

Millilmeters is a LENGTH. -That means the physical distance between the start and end of some kind of linear object.

Litres is VOLUME- a measure of content or capacity, usually expressed in units that are the cubes of linear units, or in simpler terms, what fits in a certain space.

There is no similarity between LENGTH and VOLUME. They CAN NOT be 'converted' to each other.one.