Problem: Montana i/mɒnˈtænə/ is a state in the Western region of the United States. The state's name is derived from the Spanish word montaña (mountain). Montana has several nicknames, although none official, including "Big Sky Country" and "The Treasure State", and slogans that include "Land of the Shining Mountains" and more recently "The Last Best Place". Montana is ranked 4th in size, but 44th in population and 48th in population density of the 50 United States. The western third of Montana contains numerous mountain ranges. Smaller island ranges are found throughout the state. In total, 77 named ranges are part of the Rocky Mountains.
How many ranges are part of the Rocky Mountains?
The answer is the following: 77

Problem: In 1852, Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke. The design of the Otis safety elevator is somewhat similar to one type still used today. A governor device engages knurled roller(s), locking the elevator to its guides should the elevator descend at excessive speed. He demonstrated it at the New York exposition in the Crystal Palace in a dramatic, death-defying presentation in 1854, and the first such passenger elevator was installed at 488 Broadway in New York City on March 23, 1857.
What did the govenor device engage to lock the elevator?
The answer is the following: knurled roller(s)

Problem: Improvisation once played an important role in classical music. A remnant of this improvisatory tradition in classical music can be heard in the cadenza, a passage found mostly in concertos and solo works, designed to allow skilled performers to exhibit their virtuoso skills on the instrument. Traditionally this was improvised by the performer; however, it is often written for (or occasionally by) the performer beforehand. Improvisation is also an important aspect in authentic performances of operas of Baroque era and of bel canto (especially operas of Vincenzo Bellini), and is best exemplified by the da capo aria, a form by which famous singers typically perform variations of the thematic matter of the aria in the recapitulation section ('B section' / the 'da capo' part). An example is Beverly Sills' complex, albeit pre-written, variation of Da tempeste il legno infranto from Händel's Giulio Cesare.
An example of improvisation in an opera is Beverly Sills variation of what movement of Handel's Giulio Cesare?
The answer is the following: Da tempeste il legno infranto

Problem: Until the 20th century, there was no clear record of the number of Venezuelans who emigrated to the United States. Between the 18th and early 19th centuries, there were many European immigrants who went to Venezuela, only to later migrate to the United States along with their children and grandchildren who born and/or grew up in Venezuela speaking Spanish. From 1910 to 1930, it is estimated that over 4,000 South Americans each year emigrated to the United States; however, there are few specific figures indicating these statistics. Many Venezuelans settled in the United States with hopes of receiving a better education, only to remain in there following graduation. They are frequently joined by relatives. However, since the early 1980s, the reasons for Venezuelan emigration have changed to include hopes of earning a higher salary and due to the economic fluctuations in Venezuela which also promoted an important migration of Venezuelan professionals to the US.
 Do Venezuelans still come to America for the same reasons as they did before?
The answer is the following:
since the early 1980s, the reasons for Venezuelan emigration have changed to include hopes of earning a higher salary