Given the question: Information: - Montenegro (or or ; Montenegrin: "Crna Gora" / , meaning "Black Mountain") is a sovereign state in Southeastern Europe. It has a coast on the Adriatic Sea to the south-west and is bordered by Croatia to the west, Bosnia and Herzegovina to the northwest, Serbia to the northeast, Kosovo to the east, and Albania to the south-east. Its capital and largest city is Podgorica, while Cetinje is designated as the Old Royal Capital ("prijestonica"). - Krusevac is a city and the administrative center of the Rasina District in central Serbia. It is located in the valley of West Morava, on Rasina river. According to the 2011 census, the administrative area has a population of 128,752, while the town has 58,745. - The Rasina ( Serbian Cyrillic : ) is a river in south central Serbia . The 92 km long river flows through the Rasina region , gives its name to the modern Rasina District of Serbia , and flows into the Zapadna Morava near the city of Krusevac . Its historical name is Arsen ( ) . The Rasina springs from the southern slopes of the Go mountain , near the village of Rasovka , southwest of the most famous Serbian spa , Vrnjaka Banja . The river originally flows to the southeast , around the mountains of Zeljin and Kopaonik , next to the villages of Mitrovo Polje , Bzenica , Ples , Jablanica , Grak , Toskii , Budilovina and Milentija . When the Rasina reaches the small town of Brus , it enters the upper Rasina region and continues next to the villages of Trsanovci , Lepenac and Razbojna . At this point the river reaches the western side of the Veliki Jastrebac mountain , and makes a wide , elbow turn to the north . In this part of the course , the Rasina also makes a southeast border of the Aleksandrovaka Zupa region . After the villages of Bogise and Zlatari , the Rasina has been dammed at the village of elije , with an artificial lake elije ( area 4,16 km , volume 51 million m ) . The lake is created as a part of the regulation program of the Velika Morava river and the water is also used for the Krusevac city waterworks . The lower Rasina region is densely populated ( villages of Suvaja , Majdevo , Stitare , Grkljane , Sogolj , Savrane , Gornji Stepos , Bukovica , Donji Stepos , Lipovac , Malo Golovode , Donje Golovode ) , with the administrative center of the Rasina District , Krusevac . In its lower course , the Rasina is followed by a parallel flow of the Pepeljusa river , which flows into the Zapadna Morava separately . Seven kilometers after Krusevac , the Rasina flows into the Zapadna Morava at the village of Makresane . The Rasina drains an area of 994 km , belongs to the Black Sea drainage basin and it is not navigable . - The Balkan Peninsula, or the Balkans, is a peninsula and a cultural area in Eastern and Southeastern Europe with various and disputed borders. The region takes its name from the Balkan Mountains that stretch from the Serbia-Bulgaria border to the Black Sea. - Croatia, officially the Republic of Croatia, is a sovereign state between Central Europe, Southeast Europe, and the Mediterranean. Its capital city is Zagreb, which forms one of the country's primary subdivisions, along with its twenty counties. Croatia covers and has diverse, mostly continental and Mediterranean climates. Croatia's Adriatic Sea coast contains more than a thousand islands. The country's population is 4.28million, most of whom are Croats, with the most common religious denomination being Roman Catholicism. - Belgrade is the capital and largest city of Serbia. It is located at the confluence of the Sava and Danube rivers, where the Pannonian Plain meets the Balkans. Its name translates to "White city". The urban area of the City of Belgrade has a population of 1.34 million, while over 1.65 million people live within its administrative limits. - Romania is a sovereign state located in Southeastern Europe. It borders the Black Sea, Bulgaria, Ukraine, Hungary, Serbia, and Moldova. It has an area of and a temperate-continental climate. With 19.94 million inhabitants, the country is the seventh-most-populous member state of the European Union. The capital and largest city, Bucharest, with its 1,883,425 inhabitants is the sixth-largest city in the EU. - Serbia, officially the Republic of Serbia, is a sovereign state situated at the crossroads of Central and Southeast Europe, covering the southern part of the Pannonian Plain and the central Balkans. Relative to its small territory, it is a diverse country distinguished by a "transitional" character, situated along cultural, geographic, climatic and other boundaries. Serbia is landlocked and borders Hungary to the north; Romania and Bulgaria to the east; Macedonia to the south; and Croatia, Bosnia-Herzegovina, and Montenegro to the southwest; it also claims a border with Albania through the disputed territory of Kosovo. Serbia numbers around 7 million residents, and its capital, Belgrade, ranks among the largest cities in Southeast Europe. - Bulgaria (tr. '), officially the Republic of Bulgaria (tr. '), is a country in southeastern Europe. It is bordered by Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, and the Black Sea to the east. With a territory of , Bulgaria is Europe's 16th-largest country. - Albania (; ), officially the Republic of Albania, is a sovereign state in Southeastern Europe. It has a population of 3.03 million as of 2016. Tirana is the nation's capital and largest city, followed by Durres and Vlore. Albania is located in the south-western part of the Balkan peninsula, bordered by Montenegro to the northwest, Kosovo to the northeast, the Republic of Macedonia to the east, and Greece to the south and southeast. The country has a coastline on the northern shore of the Mediterranean Sea, the Adriatic Sea to the west and the Ionian Sea to the southwest where the Albanian Riviera begins. Albania is less than from Italy, across the Strait of Otranto which connects the Adriatic Sea to the Ionian Sea. - Pannonia was an ancient province of the Roman Empire bounded north and east by the Danube, coterminous westward with Noricum and upper Italy, and southward with Dalmatia and upper Moesia. Pannonia was located over the territory of the present-day western Hungary, eastern Austria, northern Croatia, north-western Serbia, northern Slovenia, western Slovakia and northern Bosnia and Herzegovina. What is the relationship between 'rasina ' and 'west morava'?
The answer is:
mouth of the watercourse