In this task, you're given passages that contain mentions of a time duration related quesry and we are supposed to write answer to a question that involves event “frequency", which refers to how often an event is likely to be repeated. For example, "taking showers" typically occurs ~5 times a week, "going to saturday market" usually happens every few weeks/months, etc. 
 Note that a lot of the questions could have more than one correct answers. We only need a single most-likely answer. Please try to keep your "answer" as simple as possible. Concise and simple "answer" is preferred over those complex and verbose ones.  

Q: Sentence: Many globally popular sports had modern rules codified in the British Isles, including golf, association football, cricket, rugby, snooker and darts, as well as many minor sports such as croquet, bowls, pitch and putt, water polo and handball. A number of sports are popular throughout the British Isles, the most prominent of which is association football. While this is organised separately in different national associations, leagues and national teams, even within the UK, it is a common passion in all parts of the islands. Rugby union is also widely enjoyed across the islands with four national teams from England, Ireland, Scotland and Wales. The British and Irish Lions is a team chosen from each national team and undertakes tours of the southern hemisphere rugby playing nations every four years. Ireland play as a united team, represented by players from both Northern Ireland and the Republic. These national rugby teams play each other each year for the Triple Crown as part of the Six Nations Championship. Also since 2001 the professional club teams of Ireland, Scotland, Wales and Italy compete against each other in the RaboDirect Pro12. 
Question: How often do the national rugby teams play for the Triple Crown?

A: each year
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Q: Sentence: Traditionally, major college basketball teams began their seasons with a few exhibition games. They played travelling teams made up of former college players on teams such as Athletes in Action or a team sponsored by Marathon Oil. On occasion before 1992, when FIBA allowed professional players on foreign national teams, colleges played those teams in exhibitions. However, in 2003, the National Collegiate Athletic Association banned games with non-college teams. Some teams have begun scheduling exhibition games against teams in NCAA Division II and NCAA Division III, or even against colleges and universities located in Canada. Major college basketball teams still travel to other countries during the summer to play in exhibition games, although a college team is allowed one foreign tour every four years, and a maximum of ten games in each tour. 
Question: How often does the NCAA allow college teams to go overseas?

A: one foreign tour every four years
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Q: Sentence: As is sometimes common in scientific discoveries, simultaneous developments can occur, as evidenced by a number of inventors who were at work on the telephone. Over a period of 18 years, the Bell Telephone Company faced 587 court challenges to its patents, including five that went to the U.S. Supreme Court, but none was successful in establishing priority over the original Bell patent and the Bell Telephone Company never lost a case that had proceeded to a final trial stage. Bell's laboratory notes and family letters were the key to establishing a long lineage to his experiments. The Bell company lawyers successfully fought off myriad lawsuits generated initially around the challenges by Elisha Gray and Amos Dolbear. In personal correspondence to Bell, both Gray and Dolbear had acknowledged his prior work, which considerably weakened their later claims. 
Question: How many times were Bell's patents contested?

A:
587
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