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Tracks include Tucson Raceway Park and Rillito Downs. Tucson Raceway Park hosts NASCAR-sanctioned auto racing events and is one of only two asphalt short tracks in Arizona. Rillito Downs is an in-town destination on weekends in January and February each year. This historic track held the first organized quarter horse races in the world, and they are still racing there. The racetrack is threatened by development. The Moltacqua racetrack, was another historic horse racetrack located on what is now Sabino Canyon Road and Vactor Ranch Trail, but it no longer exists.
What former Tucson horse racetrack no longer exists?
A: Moltacqua racetrack

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The above explanation is merely a simple introduction to vacuum pumping, and is not representative of the entire range of pumps in use. Many variations of the positive displacement pump have been developed, and many other pump designs rely on fundamentally different principles. Momentum transfer pumps, which bear some similarities to dynamic pumps used at higher pressures, can achieve much higher quality vacuums than positive displacement pumps. Entrapment pumps can capture gases in a solid or absorbed state, often with no moving parts, no seals and no vibration. None of these pumps are universal; each type has important performance limitations. They all share a difficulty in pumping low molecular weight gases, especially hydrogen, helium, and neon.
What can momentum transfer pumps capture?
A: unanswerable

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Avignon was the seat of the papacy from 1309 to 1376. With the return of the Pope to Rome in 1378, the Papal State developed into a major secular power, culminating in the morally corrupt papacy of Alexander VI. Florence grew to prominence amongst the Italian city-states through financial business, and the dominant Medici family became important promoters of the Renaissance through their patronage of the arts. Other city states in northern Italy also expanded their territories and consolidated their power, primarily Milan and Venice. The War of the Sicilian Vespers had by the early 14th century divided southern Italy into an Aragon Kingdom of Sicily and an Anjou Kingdom of Naples. In 1442, the two kingdoms were effectively united under Aragonese control.
In what year didn't the papacy return to Rome?
A: unanswerable

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In the PAL region, which covers most of Africa, Asia, Europe, and Oceania, Twilight Princess is the best-selling entry in the Zelda series. During its first week, the game was sold with three of every four Wii purchases. The game had sold 5.82 million copies on the Wii as of March 31, 2011[update], and 1.32 million on the GameCube as of March 31, 2007[update].
How many units of the Wii version of Twilight Princess had been purchased by the end of March 2007?
A:
unanswerable