Question: How much of the continent having the mouth of the watercourse of Tikhaya Sosna does the Alps cover?

full_context: Document 1: Skhodnya River: Skhodnya River (), also known as Sukhodnya, Vkhodnya, Vykhodnya and Vskhodnya is a river in the northwest of Moscow, the second largest tributary (after the Yauza River) of the Moskva River. The length of the Skhodnya is 47 km (5 km in Moscow proper). The area of its basin is 17,2 km² (within the city). The Skhodnya originates near the village of Alabushevo (part of Zelenograd) and flows into the Moskva River near the Tushino Airfield. The Skhodnya River is connected with a derivational canal, which supplies water from the Volga River through the Khimki Reservoir (with the help of the Skhodnenskaya hydroelectric plant) to Moscow for sanitary irrigation.
Document 2: Mezha River (Western Dvina): The Mezha () is a river in Nelidovsky, Zharkovsky, and Zapadnodvinsky Districts of Tver Oblast and Velizhsky District of Smolensk Oblast in Russia. It flows out of the Valdai Hills and continues west into the Western Dvina. The town of Nelidovo and the urban-type settlement of Zharkovsky are located along the Mezha. It is long, and the area of its basin . Its main tributaries are the Bereza, the Luchesa, the Obsha, and the Yelsha (all left).
Document 3: Tikhaya Sosna River: The river has its sources in the eastern part of Belgorod Oblast, on the southeastern slopes of the Central Russian Upland. It flows in a northeasterly direction, and joins the Don some west of the town of Liski in Voronezh Oblast.
Document 4: Alps: Major European rivers flow from Switzerland, such as the Rhine, the Rhone, the Inn, the Ticino and the Po, all of which have headwaters in the Alps and flow into neighbouring countries, finally emptying into the North Sea, the Mediterranean Sea, the Adriatic Sea and the Black Sea. Other rivers such as the Danube have major tributaries flowing into them that originate in the Alps. The Rhone is second to the Nile as a freshwater source to the Mediterranean Sea; the river begins as glacial meltwater, flows into Lake Geneva, and from there to France where one of its uses is to cool nuclear power plants. The Rhine originates in a 30 square kilometre area in Switzerland and represents almost 60 percent of water exported from the country. Tributary valleys, some of which are complicated, channel water to the main valleys which can experience flooding during the snow melt season when rapid runoff causes debris torrents and swollen rivers.
Document 5: Tura River: The Tura River (), also known as Dolgaya River (Long River, ) is a historically important Siberian river which flows eastward from the central Ural Mountains into the Tobol River, a part of the Ob River basin. The main town on it is Tyumen.
Document 6: Alps: The population of the region is 14 million spread across eight countries. On the rim of the mountains, on the plateaus and the plains the economy consists of manufacturing and service jobs whereas in the higher altitudes and in the mountains farming is still essential to the economy. Farming and forestry continue to be mainstays of Alpine culture, industries that provide for export to the cities and maintain the mountain ecology.
Document 7: Battle of the Tanais River: The Battle of the Tanais River in 373 AD between the Huns and the Alans, was fought on the traditional border between Asia and Europe. The Huns were victorious.
Document 8: Battle of Mohi: The Battle of Mohi (today Muhi), also known as Battle of the Sajó River or Battle of the Tisza River (11 April 1241), was the main battle between the Mongol Empire and the Kingdom of Hungary during the Mongol invasion of Europe. It took place at Muhi, southwest of the Sajó River. After the invasion, Hungary lay in ruins. Nearly half of the inhabited places had been destroyed by the invading armies. Around 15–25 percent of the population was lost, mostly in lowland areas, especially in the Great Hungarian Plain, the southern reaches of the Hungarian plain in the area now called the Banat and in southern Transylvania.
Document 9: Yug River: The Yug () is a river in Kichmengsko-Gorodetsky, Nikolsky, and Velikoustyugsky Districts of Vologda Oblast and in Podosinovsky District of Kirov Oblast in Russia. It is long, and the area of its basin is . The Yug joins the Sukhona near the town of Veliky Ustyug, forming the Northern Dvina, one of the biggest rivers of European Russia.
Document 10: Kievan Rus': The expansion of the Rus' put further military and economic pressure on the Khazars, depriving them of territory, tributaries, and trade. In around 890, Oleg waged an indecisive war in the lands of the lower Dniester and Dnieper rivers with the Tivertsi and the Ulichs, who were likely acting as vassals of the Magyars, blocking Rus' access to the Black Sea. In 894, the Magyars and Pechenegs were drawn into the wars between the Byzantines and the Bulgarian Empire. The Byzantines arranged for the Magyars to attack Bulgarian territory from the north, and Bulgaria in turn persuaded the Pechenegs to attack the Magyars from their rear. Boxed in, the Magyars were forced to migrate further west across the Carpathian Mountains into the Hungarian plain, depriving the Khazars of an important ally and a buffer from the Rus'. The migration of the Magyars allowed Rus' access to the Black Sea, and they soon launched excursions into Khazar territory along the sea coast, up the Don river, and into the lower Volga region. The Rus' were raiding and plundering into the Caspian Sea region from 864, with the first large-scale expedition in 913, when they extensively raided Baku, Gilan, Mazandaran and penetrated into the Caucasus.
Document 11: Switzerland: Switzerland lies between latitudes 45° and 48° N, and longitudes 5° and 11° E. It contains three basic topographical areas: the Swiss Alps to the south, the Swiss Plateau or Central Plateau, and the Jura mountains on the west. The Alps are a high mountain range running across the central-south of the country, comprising about 60% of the country's total area. The majority of the Swiss population live in the Swiss Plateau. Among the high valleys of the Swiss Alps many glaciers are found, totalling an area of 1,063 square kilometres (410 sq mi). From these originate the headwaters of several major rivers, such as the Rhine, Inn, Ticino and Rhône, which flow in the four cardinal directions into the whole of Europe. The hydrographic network includes several of the largest bodies of freshwater in Central and Western Europe, among which are included Lake Geneva (also called le Lac Léman in French), Lake Constance (known as Bodensee in German) and Lake Maggiore. Switzerland has more than 1500 lakes, and contains 6% of Europe's stock of fresh water. Lakes and glaciers cover about 6% of the national territory. The largest lake is Lake Geneva, in western Switzerland shared with France. The Rhône is both the main source and outflow of Lake Geneva. Lake Constance is the second largest Swiss lake and, like the Lake Geneva, an intermediate step by the Rhine at the border to Austria and Germany. While the Rhône flows into the Mediterranean Sea at the French Camarque region and the Rhine flows into the North Sea at Rotterdam in the Netherlands, about 1000 km apart, both springs are only about 22 km apart from each other in the Swiss Alps.
Document 12: Alps: The Alps provide lowland Europe with drinking water, irrigation, and hydroelectric power. Although the area is only about 11 percent of the surface area of Europe, the Alps provide up to 90 percent of water to lowland Europe, particularly to arid areas and during the summer months. Cities such as Milan depend on 80 percent of water from Alpine runoff. Water from the rivers is used in over 500 hydroelectricity power plants, generating as much as 2900 kilowatts of electricity.
Document 13: Alps: High levels of precipitation cause the glaciers to descend to permafrost levels in some areas whereas in other, more arid regions, glaciers remain above about the 3,500 m (11,483 ft) level. The 1,817 square kilometres (702 sq mi) of the Alps covered by glaciers in 1876 had shrunk to 1,342 km2 (518 sq mi) by 1973, resulting in decreased river run-off levels. Forty percent of the glaciation in Austria has disappeared since 1850, and 30% of that in Switzerland.
Document 14: Han dynasty: During the turbulent reign of Wang Mang, Han lost control over the Tarim Basin, which was conquered by the Northern Xiongnu in AD 63 and used as a base to invade Han's Hexi Corridor in Gansu. Dou Gu (d. 88 AD) defeated the Northern Xiongnu at the Battle of Yiwulu in AD 73, evicting them from Turpan and chasing them as far as Lake Barkol before establishing a garrison at Hami. After the new Protector General of the Western Regions Chen Mu (d. AD 75) was killed by allies of the Xiongnu in Karasahr and Kucha, the garrison at Hami was withdrawn. At the Battle of Ikh Bayan in AD 89, Dou Xian (d. AD 92) defeated the Northern Xiongnu chanyu who then retreated into the Altai Mountains. After the Northern Xiongnu fled into the Ili River valley in AD 91, the nomadic Xianbei occupied the area from the borders of the Buyeo Kingdom in Manchuria to the Ili River of the Wusun people. The Xianbei reached their apogee under Tanshihuai (檀石槐) (d. AD 180), who consistently defeated Chinese armies. However, Tanshihuai's confederation disintegrated after his death.
Document 15: Battle of Adrianople: The Battle of Adrianople (9 August 378), sometimes known as the Battle of Hadrianopolis, was fought between an Eastern Roman army led by the Eastern Roman Emperor Valens and Gothic rebels (largely Thervings as well as Greutungs, non-Gothic Alans, and various local rebels) led by Fritigern. The battle took place in the vicinity of Adrianople, in the Roman province of Thracia (modern Edirne in European Turkey). It ended with an overwhelming victory for the Goths and the death of Emperor Valens.
ground_truth: 11 percent of the surface area
sub_queries: Tikhaya Sosna >> mouth of the watercourse Answer: Don
Don >> continent Answer: Europe
How much of Europe does the Alps cover? Answer: 11 percent of the surface area