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The 19th century also saw the use of red in art to create specific emotions, not just to imitate nature. It saw the systematic study of color theory, and particularly the study of how complementary colors such as red and green reinforced each other when they were placed next to each other. These studies were avidly followed by artists such as Vincent van Gogh. Describing his painting, The Night Cafe, to his brother Theo in 1888, Van Gogh wrote: "I sought to express with red and green the terrible human passions. The hall is blood red and pale yellow, with a green billiard table in the center, and four lamps of lemon yellow, with rays of orange and green. Everywhere it is a battle and antithesis of the most different reds and greens."
What occurred when red and green were put next to one another?
A: red and green reinforced each other

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Utrecht is well-connected to the Dutch road network. Two of the most important major roads serve the city of Utrecht: the A12 and A2 motorways connect Amsterdam, Arnhem, The Hague and Maastricht, as well as Belgium and Germany. Other major motorways in the area are the Almere–Breda A27 and the Utrecht–Groningen A28. Due to the increasing traffic and the ancient city plan, traffic congestion is a common phenomenon in and around Utrecht, causing elevated levels of air pollutants. This has led to a passionate debate in the city about the best way to improve the city's air quality.
What countries do the A12 and A2 connect
A: A12 and A2 motorways connect Amsterdam, Arnhem, The Hague and Maastricht, as well as Belgium and Germany

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After Madonna signed a singles deal with Sire, her debut single, "Everybody", was released in October 1982, and the second, "Burning Up", in March 1983. Both became big club hits in the United States, reaching number three on Hot Dance Club Songs chart compiled by Billboard magazine. After this success, she started developing her debut album, Madonna, which was primarily produced by Reggie Lucas of Warner Bros. However, she was not happy with the completed tracks and disagreed with Lucas' production techniques, so decided to seek additional help.
Who produced Madonna's debut album?
A: Reggie Lucas of Warner Bros

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Another common application is the control of the throttle of an internal combustion engine in conjunction with an electronic governor. In this usage, the motor works against a return spring to move the throttle in accordance with the output of the governor. The latter monitors engine speed by counting electrical pulses from the ignition system or from a magnetic pickup and, depending on the speed, makes small adjustments to the amount of current applied to the motor. If the engine starts to slow down relative to the desired speed, the current will be increased, the motor will develop more torque, pulling against the return spring and opening the throttle. Should the engine run too fast, the governor will reduce the current being applied to the motor, causing the return spring to pull back and close the throttle.
What element of a combustion engine does a governor monitor?
A:
electrical pulses