instruction:
This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
question:
Richard Nixon used national security as a basis for his expansion of power. He asserted, for example, that "the inherent power of the President to safeguard the security of the nation" authorized him to order a wiretap without a judge's warrant. Nixon also asserted that "executive privilege" shielded him from all legislative oversight; furthermore, he impounded federal funds (that is to say, he refused to spend money that Congress had appropriated for government programs). In the specific cases aforementioned, however, the Supreme Court ruled against Nixon. This was also because of an ongoing criminal investigation into the Watergate tapes, even though they acknowledged the general need for executive privilege. Since then, Nixon's successors have sometimes asserted that they may act in the interests of national security or that executive privilege shields them from Congressional oversight. Though such claims have in general been more limited than Nixon's, one may still conclude that the presidency's power has been greatly augmented since the eighteenth and nineteenth centuries.
answer:
Under what basis did Richard Nixon assert an expansion of the power of the President?


question:
The materialist view is perhaps best understood in its opposition to the doctrines of immaterial substance applied to the mind historically, famously by René Descartes. However, by itself materialism says nothing about how material substance should be characterized. In practice, it is frequently assimilated to one variety of physicalism or another.
answer:
Was René Descartes an idealist or a materialist?


question:
By 3400 BCE, the Sahara was as dry as it is today, due to reduced precipitation and higher temperatures resulting from a shift in the Earth's orbit. As a result of this aridification, it became a largely impenetrable barrier to humans, with the remaining settlements mainly being concentrated around the numerous oases that dot the landscape. Little trade or commerce is known to have passed through the interior in subsequent periods, the only major exception being the Nile Valley. The Nile, however, was impassable at several cataracts, making trade and contact by boat difficult.
answer:

By What time period was the Sahara dry like it is today?