Q:

Preposition for conversion to another unit

Which preposition should be used when I want to say a value in a different measure unit? For example, what is a correct preposition in the following sentence?

Twelve miles? I have no idea how far that is. What is it __ kilometres?

A:

It depends a bit on the verb. Often you use "in"

What is 12 miles in kilometres?
(answer: about 19 km)

But with "change" you say "Please change 12 miles to kilometres" or "into kilometres".

