1. What is the zip code for Dokdo?

2. What is the zip code of Dokdo?
3. It is 799-805
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Can we use both 'for' and' of'?

How do we read #3? Do we say'dash'? Which ones are correct?

a. seven nine nine dash eight zero five
b. seven nine nine dash eight o five
c. seven nine nine eight zero five
d. seven nine nine eight o five
e. seven double nine dash eight zero five

I'd use "for" rather than "of." I don't think "of" is incorrect, but I think "for" is better.

I think all the variations (a-e) are commonly used. I think "a" is the best one.