2. Take a look at this rock in this picture. It looks like an elephant drinking water. What is this one called? - It is called elephant Rock.

Question

3. This is a postbox, which is below/under the marker. People can send letters to the residents and police officers on Dokdo. What's the zip code for Dokdo? -It's 799-805.
(Would you check the passages? In #3, do we have to use 'below' or 'under'?)

Answer 1

These are fine.

Either below or under works well.

Answer 2

I think either is acceptable. I prefer "below".