Question: What Canadian province is the valley KMSR serves important to?
Context: Tambor Airport (IATA: TMU, ICAO: MRTR) is an airport that serves Tambor, Costa Rica.  The airport also serves important tourist destinations like Mal Pais, Santa Teresa, Montezuma, and Cabo Blanco.  It is the most important airport on the Nicoya Peninsula. The Bosphorus Express, also known as the Trans Balkan Express (Turkish: "Bosfor Ekspresi" ), is an international passenger train running between Istanbul, Turkey and Bucharest, Romania.  It runs together with the Balkans Express until Dimitrovgrad upon entering Bulgaria, where the later continues to Sofia.  The train is jointly operated by three national railways; the Turkish State Railways, the Bulgarian State Railways, and the Romanian State Railways.  The train serves important cities like Istanbul, Edirne, Russe and Bucharest.  The Bosphorus Express started service in 1971. The Swan River Valley (also: Swan Valley) is located in the western part of the Canadian province of Manitoba.  It has no clearly defined boundaries, and although it is close to the Manitoba-Saskatchewan border, the immediate area across the border is sometimes considered a part of “the valley” as it is known by locals, as well.  It is named after the Swan River, which runs through the center of the region.  It is considered a valley because of the highlands that surround it on three sides.  The Porcupine Mountains lie to the northwest, the Duck Mountains are in the south, and Thunderhill is in the western part of the region.  These features are all a part of the Manitoba Escarpment.  Thus the name Swan River Valley is somewhat misleading, as the area is not actually a river valley. KMSR (1520 AM) is a radio station in Mayville, North Dakota, serving the Red River Valley of eastern North Dakota and northwest Minnesota.  KMSR, also known as Sports Radio 1520, is on the air in the daytime only, so it signs off at sunset, and signs on again at sunrise. A substitute teacher is a person who teaches a school class when the regular teacher is unavailable; e.g., because of illness, personal leave, or other reasons.  "Substitute teacher" (usually abbreviated as "sub") is the most commonly used phrase in the United States, Canada, India and Ireland, while supply teacher is the most commonly used term in Great Britain and the Canadian province of Ontario.  Common synonyms for substitute teacher include relief teacher or casual teacher (used in Australia and New Zealand) and "emergency teacher" (used in some of the United States).  Other terms, such as "guest teacher", are also used by some schools or districts.  Regional variants in terminology are common, such as the use of the term teacher on call (T.O.C.) in the Canadian province of British Columbia and occasional in Ontario. The Okanagan Nation Alliance is a First Nations Tribal Council in the Canadian province of British Columbia, spanning the Nicola, Okanagan and Similkameen Districts of the Canadian province of British Columbia and also the Colville Indian Reservation in Washington state of the United States of America. The Midwestern Greenhouse Gas Reduction Accord (Midwestern Accord) is a regional agreement by six governors of states in the US Midwest who are members of the Midwestern Governors Association (MGA), and the premier of one Canadian province, whose purpose is to reduce greenhouse gas emissions to combat climate change.  The accord has been inactive since March 2010, when an advisory group presented a plan for action to the association with a scheduled implementation date of January 2012.  Signatories to the accord are the US states of Minnesota, Wisconsin, Illinois, Iowa, Michigan, Kansas, and the Canadian Province of Manitoba.  Observers of the accord are Indiana, Ohio, and South Dakota, as well as the Canadian Province of Ontario. Line 6 of the Beijing Subway () is a rapid transit rail line in central Beijing.  The line currently runs parallel to the north of Line 1 and the Batong Line, from Wulu in Haidian to Lucheng in Chaoyang District.  It serves important residential areas such as Changying, Chaoqing, and Dingfuzhuang, in addition to important commercial and business areas such as Financial Street and Beijing CBD.  It is planned that the line will be extended by 2015 to Shijingshan to the west.  With this extension, it is expected to be 50.67 km long with 32 stations. The Red River Valley is a region in central North America that is drained by the Red River of the North; it is part of both Canada and the United States.  Forming the border between Minnesota and North Dakota when these territories were admitted as states in the United States, this fertile valley has been important to the economies of these states and to Manitoba, Canada. Extrachromosomal DNA is any DNA that is found outside of the nucleus of a cell.  It is also referred to as extranuclear DNA or cytoplasmic DNA.  Most DNA in an individual genome is found in chromosomes but DNA found outside of the nucleus also serves important biological functions.
Answer: Manitoba