Question: Russia's biggest domestic airline is located how many km north of Chelyabinsk?

Context paragraphs:
Chelyabinsk Airport: Chelyabinsk Airport (IATA: CEK, ICAO: USCC) is an airport in Russia located 18 km north of Chelyabinsk.  It services large airliners and can park up to 51 aircraft.  It also serves as a secondary hub for S7 Airlines and Ural Airlines.

S7 Airlines: S7 Airlines, legally PJSC Siberia Airlines (Russian: ПАО «Авиакомпания "Сибирь"» "PАО Aviakompania Sibir"), is an airline headquartered in Ob, Novosibirsk Oblast, Russia, with offices in Moscow.  As of 2008, it was Russia's biggest domestic airline.  Its main bases are Domodedovo International Airport and Tolmachevo Airport.

Claino con Osteno: Claino con Osteno is a "comune" (municipality) in the Province of Como in the Italian region of Lombardy, located about 60 km north of Milan and about 20 km north of Como.  It is a small "comune" on Lake Lugano, composed of a series of small "frazioni" (hamlets): the biggest ones (Claino and Osteno) have been chosen for the municipal name.

Chulman Airport: Chulman Neryungri Airport (IATA: NER, ICAO: UELL) (Russian: Аэропорт Нерюнгри (Чульман) ) is a civilian airport in Yakutia, Russia located 8 km north of Chulman and 40 km north of Neryungri.

Cửa Lò: Cửa Lò is a town district of Nghệ An Province, in the North Central Coast region of Vietnam.  As of 2003 the district had a population of 46,185.  The district covers an area of 28 km².  Cua Lo is located 290 km south of Ha Noi, 1400 km north of Ho Chi Minh City and 16 km northeast of Vinh City.  The district capital lies at Cửa Lò.  Cua Lo is one of the most beautiful beaches in Vietnam.  Thanks to beautiful scenery, fine white sand, sloping slope and moderate salinity, Cua Lo attracts many domestic and foreign tourists to visit and relax.

Mrzeżyno: Mrzeżyno (German: "Deep", or "Treptower Deep", after 1930 often "Regamünde") is a village with a fishing seaport in Gryfice County.  This is also a health resort with a lots of pensions, campsites and spa.  It is located near the estuary of the Rega river.  The village has a popular beach.  Every year in July and August, Mrzeżyno is visited by many Polish and German tourists.  The right riverside is more developed than left, where there is only one settlement.  The population numbers 1,727.  The village is situated by a special area of the conservation of nature according to the European Union's program Natura 2000.  It lies approximately 10 km north of Trzebiatów, 27 km north of Gryfice, and 94 km north-east of the regional capital Szczecin.

Ilmen Nature Reserve: Ilmen Nature Reserve (Russian: Ильменский заповедник ) (also Ilmensky) is a Russian 'zapovednik' (strict nature reserve) that was created by decree of Vladimir Lenin, in 1920 as a mineralogical nature reserve.  It is the site of deposits of many rare-earth minerals - 16 minerals were first discovered here, including Ilmenite (named for the site), Monazite, Cancrinite, and Samarskite-(Y).  There have been over 400 mines in the area over the years.  The Reserve's geological museum is one of the largest in Russia.  The forest cover is pine and larch forest on low hills of the Ilmensky Mountains and foothill ridges on east side of the south Ural Mountains.  The reserve is situated just north and east of the city of Miass, in the Chebarkulsky District of Chelyabinsk Oblast.  It is also 20 kkm east of Taganay National Park and 75 km west of Chelyabinsk.

Ukrainka (air base): Ukrainka (also known as Ookrainka and Seryshevo) is one of Russia's largest strategic Long Range Aviation bases in the Russian Far East.  Located in Amur Oblast, Russia, 28 km north of Belogorsk, and 8km north of the town of Seryshevo, it is a major nuclear bomber base, with large tarmacs and nearly 40 revetments.

Janardanaswamy Temple: Janardana Swami Temple is a 2000-year-old temple situated in Varkala, Thiruvananthapuram.  It is also known as Varkala Temple.  Janardana Swami is a form of Lord Vishnu.  It is a very well known temple in Kerala about 10.9 km west of Kallambalam on NH 66 near sea, 25 km north of Thiruvananthapuram city, 13 km south of famous backwater destination Paravur and 2 km from Varkala Sivagiri railway station,14 km north west of biggest town Attingal.  It is situated near the Arabian sea shore.It is referred to as Dakshin Kashi (Benares of the south).  The temple is located close to the Papanasam beach, which is considered to have medicinal properties since the waters wash the nearby medicinal plants.  It is also an important Ayurveda treatment center.  The temple has an ancient bell removed from a shipwreck, donated by the captain of the Dutch vessel which sank near Varkala without causing any casualties.

Khukha: Khukha is a big village in Jhelum District, Punjab, Pakistan.  It is a Union Council, an administrative subdivision, of Jhelum Tehsil and is a "model" village.  It is located at 33°0'0N 73°33'0E with an altitude of 259 metres (853 feet) and lies 7 km west of Dina, 5 km north of Rohtas and 10 km north east of Tilla Jogian.  Many people from here have emigrated to all over the world.  Approximately 500 live in the UK.

Supporting paragraphs: Chelyabinsk Airport S7 Airlines
Answer: 18 km