Problem: Department store:

The first department stores Lane Crawford was opened in 1850 by Scots Thomas Ash Lane and Ninian Crawford on Des Voeux Road, Hong Kong Island. At the beginning, the store mainly catered visiting ships' crews as well as British Navy staff and their families. In 1900, the first ethnic-Chinese owned Sincere Department Store was opened by Ma Ying Piu, who returned from Australia and inspired by David Jones. In 1907, another former Hong Kong expatriate in Australia, the Kwok's family, returned to Hong Kong and founded Wing On.

What year did Lane Crawford open?
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A: 1850

Problem: The simplest model capacitor consists of two thin parallel conductive plates separated by a dielectric with permittivity . This model may also be used to make qualitative predictions for other device geometries. The plates are considered to extend uniformly over an area A and a charge density = Q/A exists on their surface. Assuming that the length and width of the plates are much greater than their separation d, the electric field near the centre of the device will be uniform with the magnitude E = /. The voltage is defined as the line integral of the electric field between the plates
In an ideal model of a capacitor, what must be assumed about the size of the plates?
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Answer: much greater than their separation d

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Subsequent to these developments, Randall Collins (2004) formulated his interaction ritual theory by drawing on Durkheim's work on totemic rituals that was extended by Goffman (1964/2013; 1967) into everyday focused encounters. Based on interaction ritual theory, we experience different levels or intensities of emotional energy during face-to-face interactions. Emotional energy is considered to be a feeling of confidence to take action and a boldness that one experiences when they are charged up from the collective effervescence generated during group gatherings that reach high levels of intensity.
What is the term for a feeling of confidence to not take action?
A: unanswerable

Context and question: Clothing can and has in history been made from a very wide variety of materials. Materials have ranged from leather and furs, to woven materials, to elaborate and exotic natural and synthetic fabrics. Not all body coverings are regarded as clothing. Articles carried rather than worn (such as purses), worn on a single part of the body and easily removed (scarves), worn purely for adornment (jewelry), or those that serve a function other than protection (eyeglasses), are normally considered accessories rather than clothing, as are footwear and hats.
What is an example of something that serves a function other than protection?
Answer: eyeglasses

Question: The central part of the Sahara is hyperarid, with little to no vegetation. The northern and southern reaches of the desert, along with the highlands, have areas of sparse grassland and desert shrub, with trees and taller shrubs in wadis where moisture collects. In the central, hyperarid part, there are many subdivisions of the great desert such as the Tanezrouft, the Tenere, the Libyan Desert, the Eastern Desert, the Nubian Desert and others. These absolute desert regions are characterized by their extreme aridity, and some years can pass without any rainfall.
Is there an answer to this question: What is the central part of the Sahara Desert?

Answer: hyperarid

Problem: Computer security:

One use of the term "computer security" refers to technology that is used to implement secure operating systems. In the 1980s the United States Department of Defense (DoD) used the "Orange Book" standards, but the current international standard ISO/IEC 15408, "Common Criteria" defines a number of progressively more stringent Evaluation Assurance Levels. Many common operating systems meet the EAL4 standard of being "Methodically Designed, Tested and Reviewed", but the formal verification required for the highest levels means that they are uncommon. An example of an EAL6 ("Semiformally Verified Design and Tested") system is Integrity-178B, which is used in the Airbus A380 and several military jets.

What makes it difficult for systems to use the EAL4 standard?
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A:
unanswerable