This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
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Question: Passage: Uranium is a naturally occurring element that can be found in low levels within all rock, soil, and water. Uranium is the 51st element in order of abundance in the Earth's crust. Uranium is also the highest-numbered element to be found naturally in significant quantities on Earth and is almost always found combined with other elements. Along with all elements having atomic weights higher than that of iron, it is only naturally formed in supernovae. The decay of uranium, thorium, and potassium-40 in the Earth's mantle is thought to be the main source of heat that keeps the outer core liquid and drives mantle convection, which in turn drives plate tectonics. Question: Where does uranium rank among elements in terms of its abundance in the Earth's crust?

Answer: 51st


Question: Passage: The "snug", sometimes called the smoke room, was typically a small, very private room with access to the bar that had a frosted glass external window, set above head height. A higher price was paid for beer in the snug and nobody could look in and see the drinkers. It was not only the wealthy visitors who would use these rooms. The snug was for patrons who preferred not to be seen in the public bar. Ladies would often enjoy a private drink in the snug in a time when it was frowned upon for women to be in a pub. The local police officer might nip in for a quiet pint, the parish priest for his evening whisky, or lovers for a rendezvous. Question: What was the relationship between the price of beer in the smoke room versus the rest of the bar?

Answer: higher


Question: Passage: West of the Rocky Mountains lies the Intermontane Plateaus (also known as the Intermountain West), a large, arid desert lying between the Rockies and the Cascades and Sierra Nevada ranges. The large southern portion, known as the Great Basin, consists of salt flats, drainage basins, and many small north-south mountain ranges. The Southwest is predominantly a low-lying desert region. A portion known as the Colorado Plateau, centered around the Four Corners region, is considered to have some of the most spectacular scenery in the world. It is accentuated in such national parks as Grand Canyon, Arches, Mesa Verde National Park and Bryce Canyon, among others. Other smaller Intermontane areas include the Columbia Plateau covering eastern Washington, western Idaho and northeast Oregon and the Snake River Plain in Southern Idaho. Question: What type of flats compose the Great Basin?

Answer:
salt flats