Problem: There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 32. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mCu the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by , whereas those with a mass number below 64 decay by +. 64Cu, which has a half-life of 12.7 hours, decays both ways.
Which isotope makes up about 69% of natural copper?
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Answer: 63Cu

Problem: The Russian Soviet Federative Socialist Republic (Russian SFSR or RSFSR; Russian: , tr. Rossiyskaya Sovetskaya Federativnaya Sotsialisticheskaya Respublika listen (helpinfo)) commonly referred to as Soviet Russia or simply as Russia, was a sovereign state in 191722, the largest, most populous, and most economically developed republic of the Soviet Union in 192291 and a sovereign part of the Soviet Union with its own legislation in 199091. The Republic comprised sixteen autonomous republics, five autonomous oblasts, ten autonomous okrugs, six krais, and forty oblasts. Russians formed the largest ethnic group. To the west it bordered Finland, Norway and Poland; and to the south, China, Mongolia and North Korea whilst bordering the Arctic Ocean to the north, the Pacific Ocean to the east and the Black sea and Caspian Sea to the south. Within the USSR, it bordered the Baltic republics (Lithuania, Latvia and Estonia), the Byelorussian SSR and the Ukrainian SSR to the west. To the south it bordered the Georgian, Azerbaijan and Kazakh SSRs.
Which union did Russia belong to before 1922?
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Answer: unanswerable

Problem: The Qur'an relates detailed narrative accounts of Maryam (Mary) in two places, Qur'an 3:3547 and 19:1634. These state beliefs in both the Immaculate Conception of Mary and the Virgin birth of Jesus. The account given in Sura 19 is nearly identical with that in the Gospel according to Luke, and both of these (Luke, Sura 19) begin with an account of the visitation of an angel upon Zakariya (Zecharias) and Good News of the birth of Yahya (John), followed by the account of the annunciation. It mentions how Mary was informed by an angel that she would become the mother of Jesus through the actions of God alone.
Who was visited by an angel in Sura 19 of the Qur'an?
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Answer:
Zakariya