Problem: Computer security:

Denial of service attacks are designed to make a machine or network resource unavailable to its intended users. Attackers can deny service to individual victims, such as by deliberately entering a wrong password enough consecutive times to cause the victim account to be locked, or they may overload the capabilities of a machine or network and block all users at once. While a network attack from a single IP address can be blocked by adding a new firewall rule, many forms of Distributed denial of service (DDoS) attacks are possible, where the attack comes from a large number of points – and defending is much more difficult. Such attacks can originate from the zombie computers of a botnet, but a range of other techniques are possible including reflection and amplification attacks, where innocent systems are fooled into sending traffic to the victim.

What is done to a password to lock out all users at once?
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A: unanswerable


Problem: Dialect:

There is no universally accepted criterion for distinguishing two different languages from two dialects (i.e. varieties) of the same language. A number of rough measures exist, sometimes leading to contradictory results. The distinction is therefore subjective and depends on the user's frame of reference. For example, there is discussion about if the Limón Creole English must be considered as "a kind" of English or a different language. This creole is spoken in the Caribbean coast of Costa Rica (Central America) by descendant of Jamaican people. The position that Costa Rican linguists support depends on the University they belong.

Who speaks Costa Rican Creole?
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A: unanswerable


Problem: God:

St. Anselm's approach was to define God as, "that than which nothing greater can be conceived". Famed pantheist philosopher Baruch Spinoza would later carry this idea to its extreme: "By God I understand a being absolutely infinite, i.e., a substance consisting of infinite attributes, of which each one expresses an eternal and infinite essence." For Spinoza, the whole of the natural universe is made of one substance, God, or its equivalent, Nature. His proof for the existence of God was a variation of the Ontological argument.

Spinoza believed that the universe was made up of one substance which is?
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A: God


Problem: Uranium:

It is estimated that 5.5 million tonnes of uranium exists in ore reserves that are economically viable at US$59 per lb of uranium, while 35 million tonnes are classed as mineral resources (reasonable prospects for eventual economic extraction). Prices went from about $10/lb in May 2003 to $138/lb in July 2007. This has caused a big increase in spending on exploration, with US$200 million being spent worldwide in 2005, a 54% increase on the previous year. This trend continued through 2006, when expenditure on exploration rocketed to over $774 million, an increase of over 250% compared to 2004. The OECD Nuclear Energy Agency said exploration figures for 2007 would likely match those for 2006.

How much economically viable uranium is there in ore reserves, in billions of tonnes?
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A:
unanswerable