paragraph_text: Melodifestivalen 1981 was the selection for the 21st song to represent Sweden at the Eurovision Song Contest. It was the 20th time that this system of picking a song had been used. 90 songs were submitted to SVT for the competition. The final was broadcast on TV1 but was not broadcast on radio. It was the second time that Lasse Holm and Kikki Danielsson had been beaten into second place by Björn Skifs, after 1978.

paragraph_text: The Silent Battle is a 1939 British thriller film directed by Herbert Mason and starring Rex Harrison, Valerie Hobson and John Loder. It is also known by the alternative titles Continental Express and Peace in our Time. It was inspired by the novel "Le Poisson Chinois" by Jean Bommart. Secret agents try to defeat terrorists on the Orient Express.

paragraph_text: In 2018, the Social Security Wage Base was $128,400 and the Social Security tax rate was 6.20% paid by the employee and 6.20% paid by the employer. A person with $10,000 of gross income had $620.00 withheld as Social Security tax from his check and the employer sent an additional $620.00. A person with $130,000 of gross income in 2017 incurred Social Security tax of $7,886.40 (resulting in an effective rate of approximately 6.07% - the rate was lower because the income was more than the 2017 ``wage base '', see below), with $7,886.40 paid by the employer. A person who earned a million dollars in wages paid the same $7,886.40 in Social Security tax (resulting in an effective rate of approximately 0.79%), with equivalent employer matching. In the cases of the $130 k and $1 m earners, each paid the same amount into the social security system, and both will take the same out of the social security system.

paragraph_text: Köppen - Geiger climate classification system classifies its climate as hot desert (BWh). Luxor, Minya, Sohag, Qena and Asyut have the widest difference of temperatures between days and nights of any city in Egypt, with almost 16 ° C (29 ° F) difference. Sohag is one of the warmest places in Egypt due to its place in the east side of Sahara in North Africa. Sohag is ranked the 5th driest place in Egypt and the 9th globally. Also ranked 4th warmest place in Egypt and 296th globally.

paragraph_text: The differences between fungi and other organisms regarded as plants had long been recognised by some; Haeckel had moved the fungi out of Plantae into Protista after his original classification, but was largely ignored in this separation by scientists of his time. Robert Whittaker recognized an additional kingdom for the Fungi. The resulting five - kingdom system, proposed in 1969 by Whittaker, has become a popular standard and with some refinement is still used in many works and forms the basis for new multi-kingdom systems. It is based mainly upon differences in nutrition; his Plantae were mostly multicellular autotrophs, his Animalia multicellular heterotrophs, and his Fungi multicellular saprotrophs. The remaining two kingdoms, Protista and Monera, included unicellular and simple cellular colonies. The five kingdom system may be combined with the two empire system:

paragraph_text: While considered "alternative" today, most alternative systems have existed since ancient times. After the public school system was widely developed beginning in the 19th century, some parents found reasons to be discontented with the new system. Alternative education developed in part as a reaction to perceived limitations and failings of traditional education. A broad range of educational approaches emerged, including alternative schools, self learning, homeschooling and unschooling. Example alternative schools include Montessori schools, Waldorf schools (or Steiner schools), Friends schools, Sands School, Summerhill School, The Peepal Grove School, Sudbury Valley School, Krishnamurti schools, and open classroom schools. Charter schools are another example of alternative education, which have in the recent years grown in numbers in the US and gained greater importance in its public education system.

paragraph_text: The National Conference of State Legislatures held in Washington D.C. stated in a 2014 overview that many supporters for affirmative action argue that policies stemming from affirmative action help to open doors for historically excluded groups in workplace settings and higher education. Workplace diversity has become a business management concept in which employers actively seek to promote an inclusive workplace. By valuing diversity, employers have the capacity to create an environment in which there is a culture of respect for individual differences as well as the ability to draw in talent and ideas from all segments of the population. By creating this diverse workforce, these employers and companies gain a competitive advantage in an increasingly global economy. According to the U.S. Equal Employment Opportunity Commission, many private sector employers have concluded that a diverse workforce makes a "company stronger, more profitable, and a better place to work." Therefore, these diversity promoting policies are implemented for competitive reasons rather than as a response to discrimination, but have shown the value in having diversity.

paragraph_text: After a series of test transmissions and special broadcasts that began in August 1936, the BBC Television Service officially launched on 2 November 1936 from a converted wing of Alexandra Palace in London. ``Ally Pally ''housed two studios, various scenery stores, make - up areas, dressing rooms, offices, and the transmitter itself, which then broadcast on the VHF band. BBC television initially used two systems on alternate weeks: the 240 - line Baird intermediate film system and the 405 - line Marconi - EMI system. The use of both formats made the BBC's service the world's first regular high - definition television service; it broadcast from Monday to Saturday between 15: 00 and 16: 00, and 21: 00 and 22: 00. The first programme broadcast -- and thus the first ever, on a dedicated TV channel -- was`` Opening of the BBC Television Service'' at 15: 00. The first major outside broadcast was the coronation of King George VI and Queen Elizabeth in May 1937.

paragraph_text: After a series of test transmissions and special broadcasts that began in August, regular BBC television broadcasts officially resumed on 1 October 1936, from a converted wing of Alexandra Palace in London, which housed two studios, various scenery stores, make-up areas, dressing rooms, offices, and the transmitter itself, now broadcasting on the VHF band. BBC television initially used two systems, on alternate weeks: the 240-line Baird intermediate film system and the 405-line Marconi-EMI system, each making the BBC the world's first regular high-definition television service, broadcasting Monday to Saturday from 15:00 to 16:00 and 21:00 to 22:00.

paragraph_text: Evangelische Omroep (EO, English: "Evangelical Broadcasting") is one of the twelve member-based broadcasting associations contributing to the Netherlands Public Broadcasting system. It has as its mission to bring people into contact with Jesus Christ and its statement of faith is a form of Evangelicalism. EO is one of the few broadcasting associations in the "pillarized" Dutch broadcasting system to have remained totally faithful to its religious roots. For a long time every one of its programmes made reference to God and to the Christian religion, although this is less often the case in the 21st century.

paragraph_text: The BBC began its own regular television programming from the basement of Broadcasting House, London, on 22 August 1932. The studio moved to larger quarters in 16 Portland Place, London, in February 1934, and continued broadcasting the 30-line images, carried by telephone line to the medium wave transmitter at Brookmans Park, until 11 September 1935, by which time advances in all-electronic television systems made the electromechanical broadcasts obsolete.

paragraph_text: Bror Rexed (June 19, 1914 – August 21, 2002) was a Swedish neuroscientist and professor at Uppsala University. Internationally, he is best known today for his development of the system now known as Rexed laminae, but in Sweden, he is also known for his involvement in the "du-reformen" of the Swedish language.

paragraph_text: The PIN Code system was introduced on 15 August 1972 by Shriram Bhikaji Velankar, an additional secretary in the Union Ministry of Communications. The system was introduced to simplify the manual sorting and delivery of mail by eliminating confusion over incorrect addresses, similar place names and different languages used by the public.

paragraph_text: The two systems were to run on a trial basis for six months; early television sets supported both resolutions. However, the Baird system, which used a mechanical camera for filmed programming and Farnsworth image dissector cameras for live programming, proved too cumbersome and visually inferior, and ended with closedown (at 22:00) on Saturday 13 February 1937.

paragraph_text: The Obusier de 6 pouces Gribeauval or 6-inch howitzer was a French artillery piece and part of a system established by Jean Baptiste Vaquette de Gribeauval. The Old French inch () was actually 1.066 English inches long so the weapon can accurately be described as a 6.4-inch howitzer. The Gribeauval system included the 6-inch howitzer, the light Canon de 4 Gribeauval, medium Canon de 8 Gribeauval and the heavy Canon de 12 Gribeauval. Superseding the older Vallière system, the Gribeauval system was introduced in 1765 and the guns were first used during the American Revolutionary War. The most comprehensive employment of Gribeauval guns occurred during the French Revolutionary Wars and the Napoleonic Wars. Two 6-inch howitzers were often added to four or six cannons to make up a battery of artillery in Napoleon's armies. The 6-inch howitzer was capable of firing an exploding shell at long-range targets or a canister shot at close-range enemy personnel. Starting in 1803, the Year XI system partly replaced the Gribeauval artillery, but it was not until 1829 that the Gribeauval system was wholly superseded by the Valée system.

paragraph_text: Publishers from different factions of the Latter Day Saint movement have published different chapter and verse notation systems. The two most significant are the LDS system, introduced in 1879, and the RLDS system, which is based on the original 1830 chapter divisions.

paragraph_text: Antonius Rex, is an Italian progressive rock band founded in 1974 in Milan by Antonio Bartoccetti. It is the same band as Jacula with a different name.

paragraph_text: Rex Brough "aka King John and the Red King" (born 1960 in Meriden, Warwickshire) is an English record producer and editor of radio programmes, mainly for the BBC.

paragraph_text: The first television broadcast in Australia took place on 30 September 1929 at the Menzies Hotel in Melbourne, using the electro - mechanical Radiovision system. Other transmissions took place in the city over the next few weeks. Also in 1929, the Baird system was used on 3DB, 3UZ and 2UE.

paragraph_text: The basis for classical economics forms Adam Smith's An Inquiry into the Nature and Causes of the Wealth of Nations, published in 1776. Smith criticized mercantilism, advocating a system of free trade with division of labour. He postulated an "invisible hand" that regulated economic systems made up of actors guided only by self-interest. Karl Marx developed an alternative economic theory, called Marxian economics. Marxian economics is based on the labor theory of value and assumes the value of good to be based on the amount of labor required to produce it. Under this assumption, capitalism was based on employers not paying the full value of workers labor to create profit. The Austrian school responded to Marxian economics by viewing entrepreneurship as driving force of economic development. This replaced the labor theory of value by a system of supply and demand.

Question: For how long did Rex Brough's employer alternate different broadcasting systems?
Answer: six months