Question: "when did Ivashko's resignation become official" Context: "On June 22, 1990, Volodymyr Ivashko withdrew his candidacy for leader of the Communist Party of Ukraine in view of his new position in parliament. Stanislav Hurenko was elected first secretary of the CPU. On July 11, Ivashko resigned from his post as chairman of the Ukrainian Parliament after he was elected deputy general secretary of the Communist Party of the Soviet Union. The Parliament accepted the resignation a week later, on July 18. On July 16 Parliament overwhelmingly approved the Declaration on State Sovereignty of Ukraine - with a vote of 355 in favour and four against. The people's deputies voted 339 to 5 to proclaim July 16 a Ukrainian national holiday." Answer:
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Answer: July 18

Question: "who decended to the pharaohs land?" Context: "The crowd roared in approval and Arab audiences were electrified. The assassination attempt backfired, quickly playing into Nasser's hands. Upon returning to Cairo, he ordered one of the largest political crackdowns in the modern history of Egypt, with the arrests of thousands of dissenters, mostly members of the Brotherhood, but also communists, and the dismissal of 140 officers loyal to Naguib. Eight Brotherhood leaders were sentenced to death, although the sentence of its chief ideologue, Sayyid Qutb, was commuted to a 15-year imprisonment. Naguib was removed from the presidency and put under house arrest, but was never tried or sentenced, and no one in the army rose to defend him. With his rivals neutralized, Nasser became the undisputed leader of Egypt." Answer:
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Answer: Nasser

Question: "How can the refraction index of a piece of glass be reduced?" Context: "Glass has the ability to refract, reflect, and transmit light following geometrical optics, without scattering it. It is used in the manufacture of lenses and windows. Common glass has a refraction index around 1.5. This may be modified by adding low-density materials such as boron, which lowers the index of refraction (see crown glass), or increased (to as much as 1.8) with high-density materials such as (classically) lead oxide (see flint glass and lead glass), or in modern uses, less toxic oxides of zirconium, titanium, or barium. These high-index glasses (inaccurately known as "crystal" when used in glass vessels) cause more chromatic dispersion of light, and are prized for their diamond-like optical properties." Answer:
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Answer:
by adding low-density materials