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The Vikings established Danelaw over much of the eastern and northern part of England with its boundary roughly stretching from London to Chester. It was an area of political and geographical control imposed by the Viking incursions which was formally agreed to by the Danish warlord, Guthrum and west-Saxon king, Alfred the Great in 886 AD. The Anglo-Saxon Chronicle recorded that London was "refounded" by Alfred the Great in 886. Archaeological research shows that this involved abandonment of Lundenwic and a revival of life and trade within the old Roman walls. London then grew slowly until about 950, after which activity increased dramatically.

What was Danelaw?
Answer: political and geographical control imposed by the Viking incursions
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Literacy rate in the Muslim world varies. Some members such as Kuwait, Kazakhstan, Tajikistan and Turkmenistan have over 97% literacy rates, whereas literacy rates are the lowest in Mali, Afghanistan, Chad and parts of Africa. In 2015, the International Islamic News Agency reported that nearly 37% of the population of the Muslim world is unable to read or write, basing that figure on reports from the Organisation of Islamic Cooperation and the Islamic Educational, Scientific and Cultural Organization.

Which regions have the lowest rate of literacy in the Muslim world?
Answer: Mali, Afghanistan, Chad and parts of Africa
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A P-N junction can convert absorbed light energy into a proportional electric current. The same process is reversed here (i.e. the P-N junction emits light when electrical energy is applied to it). This phenomenon is generally called electroluminescence, which can be defined as the emission of light from a semi-conductor under the influence of an electric field. The charge carriers recombine in a forward-biased P-N junction as the electrons cross from the N-region and recombine with the holes existing in the P-region. Free electrons are in the conduction band of energy levels, while holes are in the valence energy band. Thus the energy level of the holes will be lesser than the energy levels of the electrons. Some portion of the energy must be dissipated in order to recombine the electrons and the holes. This energy is emitted in the form of heat and light.

Whose energy levels are lower than the electrons in the electroluminescence process?
Answer:
holes existing in the P-region