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.  

Sentence: Winters are cold and damp, and prevailing wind patterns that blow offshore minimize the moderating effects of the Atlantic Ocean; yet the Atlantic and the partial shielding from colder air by the Appalachians keep the city warmer in the winter than inland North American cities at similar or lesser latitudes such as Pittsburgh, Cincinnati, and Indianapolis. The daily mean temperature in January, the area's coldest month, is 32.6 °F (0.3 °C); however, temperatures usually drop to 10 °F (−12 °C) several times per winter, and reach 50 °F (10 °C) several days each winter month. Spring and autumn are unpredictable and can range from chilly to warm, although they are usually mild with low humidity. Summers are typically warm to hot and humid, with a daily mean temperature of 76.5 °F (24.7 °C) in July and an average humidity level of 72%. Nighttime conditions are often exacerbated by the urban heat island phenomenon, while daytime temperatures exceed 90 °F (32 °C) on average of 17 days each summer and in some years exceed 100 °F (38 °C). In the warmer months, the dew point, a measure of atmospheric moisture, ranges from 57.3 °F (14.1 °C) in June to 62.0 °F (16.7 °C) in August. Extreme temperatures have ranged from −15 °F (−26 °C), recorded on February 9, 1934, up to 106 °F (41 °C) on July 9, 1936. 
Question: On average, how often do New York temperatures exceed 90 degrees Fahrenheit each year?
17

Sentence: Despite their close genetic relationship and the ability to inter-breed, there are a number of diagnostic features to distinguish the gray wolves from domestic dogs. Domesticated dogs are clearly distinguishable from wolves by starch gel electrophoresis of red blood cell acid phosphatase. The tympanic bullae are large, convex and almost spherical in gray wolves, while the bullae of dogs are smaller, compressed and slightly crumpled. Compared to equally sized wolves, dogs tend to have 20% smaller skulls and 30% smaller brains.:35 The teeth of gray wolves are also proportionately larger than those of dogs; the premolars and molars of wolves are much less crowded and have more complex cusp patterns. Wolves do not have dewclaws on their back legs, unless there has been admixture with dogs. Dogs lack a functioning pre-caudal gland, and most enter estrus twice yearly, unlike gray wolves which only do so once a year. Dogs require fewer calories to function than wolves. The dog's limp ears may be the result of atrophy of the jaw muscles. The skin of domestic dogs tends to be thicker than that of wolves, with some Inuit tribes favoring the former for use as clothing due to its greater resistance to wear and tear in harsh weather. 
Question: How often do female wolves enter estrus?
once a year.

Sentence: DST's clock shifts have the obvious disadvantage of complexity. People must remember to change their clocks; this can be time-consuming, particularly for mechanical clocks that cannot be moved backward safely. People who work across time zone boundaries need to keep track of multiple DST rules, as not all locations observe DST or observe it the same way. The length of the calendar day becomes variable; it is no longer always 24 hours. Disruption to meetings, travel, broadcasts, billing systems, and records management is common, and can be expensive. During an autumn transition from 02:00 to 01:00, a clock reads times from 01:00:00 through 01:59:59 twice, possibly leading to confusion. 
Question: During the fall time shift from 02:00 to 01:00, how many times will a clock show the times between 01:00:00 and 01:59:59?

twice