Problem: Energy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years respectively). Most countries with large rail networks do not have significant oil reserves and those that did, like the United States and Britain, have exhausted much of their reserves and have suffered declining oil output for decades. Therefore, there is also a strong economic incentive to substitute other fuels for oil. Rail electrification is often considered an important route towards consumption pattern reform. However, there are no reliable, peer-reviewed studies available to assist in rational public debate on this critical issue, although there are untranslated Soviet studies from the 1980s.
What type of natural resources is more scarce?
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Answer: liquid fuel

Problem: Some titles have a Biblical basis, for instance the title Queen Mother has been given to Mary since she was the mother of Jesus, who was sometimes referred to as the "King of Kings" due to his lineage of King David. The biblical basis for the term Queen can be seen in the Gospel of Luke 1:32 and the Book of Isaiah 9:6, and Queen Mother from 1 Kings 2:19-20 and Jeremiah 13:18-19. Other titles have arisen from reported miracles, special appeals or occasions for calling on Mary, e.g., Our Lady of Good Counsel, Our Lady of Navigators or Our Lady of Ransom who protects captives.
Who was the mother of Jesus?
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Answer: Mary

Problem: The Strategic Defence and Security Review 2015 included 178 billion investment in new equipment and capabilities. The review set a defence policy with four primary missions for the Armed Forces:
When did the Armed Forces take part in four primary missions?
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Answer:
unanswerable