An import is something our country wants, and pays another country to ship in. An export is something another country wants, and pays our country to ship out.
discoverable means you can "find" something even if it is not readily visible, and visible means you see something that is very apparent. So its a big difference between the two. As an example:The...
visible trade refers to the import or export of physical goods (things you can see) for eg. foodinvisible trade is the opposite , the import or export of services eg.tourism