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: These limitations have caused problems. For example, before 2005, DST in Israel varied each year and was skipped some years. Windows 95 used rules correct for 1995 only, causing problems in later years. In Windows 98, Microsoft marked Israel as not having DST, forcing Israeli users to shift their computer clocks manually twice a year. The 2005 Israeli Daylight Saving Law established predictable rules using the Jewish calendar but Windows zone files could not represent the rules' dates in a year-independent way. Partial workarounds, which mishandled older time stamps, included manually switching zone files every year and a Microsoft tool that switches zones automatically. In 2013, Israel standardized its daylight saving time according to the Gregorian calendar. 
Question: How often would Israeli users running Windows 98 need to manually adjust the time on their machines to stay current?

A: twice a year
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Q: Sentence: Sometimes circumstances such as a good breeding season followed by a food source failure the following year lead to irruptions in which large numbers of a species move far beyond the normal range. Bohemian waxwings Bombycilla garrulus well show this unpredictable variation in annual numbers, with five major arrivals in Britain during the nineteenth century, but 18 between the years 1937 and 2000. Red crossbills Loxia curvirostra too are irruptive, with widespread invasions across England noted in 1251, 1593, 1757, and 1791. 
Question: How many times did Bohemian waxwings come to Britain in the nineteeth century?

A: five
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Q: Sentence: More recently, films such as Das Boot (1981), The Never Ending Story (1984) Run Lola Run (1998), Das Experiment (2001), Good Bye Lenin! (2003), Gegen die Wand (Head-on) (2004) and Der Untergang (Downfall) (2004) have enjoyed international success. In 2002 the Academy Award for Best Foreign Language Film went to Caroline Link's Nowhere in Africa, in 2007 to Florian Henckel von Donnersmarck's The Lives of Others. The Berlin International Film Festival, held yearly since 1951, is one of the world's foremost film and cinema festivals. 
Question: How often is the Berlin International Film Festival held?

A:
yearly
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