Final answer:
Costa Rica and Nicaragua share the San Juan River on their border, while the Coco River is primarily in Nicaragua. Costa Rica is a peaceful, democratic nation with a stable economy.
Step-by-step explanation:
The Coco River is mainly located in Nicaragua and the San Juan River forms part of the border between Costa Rica and Nicaragua. Costa Rica is known for not having an army and for being a stable democratic country with a growing economy, often being nicknamed the Switzerland of Central America. It's bordered by Nicaragua to the north, where the Coco River can be found, and has the San Juan River on its northern border as well. Meanwhile, the economy of Central America has been significantly influenced by US companies, particularly in the realms of fruit and coffee production.