Question: Question: "What is constant?" Context: "The Faraday constant F is the charge of one mole of electrons, equal to the Avogadro constant NA multiplied by the elementary charge e. It can be determined by careful electrolysis experiments, measuring the amount of silver dissolved from an electrode in a given time and for a given electric current. In practice, it is measured in conventional electrical units, and so given the symbol F90. Substituting the definitions of NA and e, and converting from conventional electrical units to SI units, gives the relation to the Planck constant." Answer:
Answer: the Planck

Question: Question: "During what century did Hindu Shahis take command of the dynasties?" Context: "The Kabul Shahi dynasties ruled the Kabul Valley and Gandhara (modern-day Pakistan and Afghanistan) from the decline of the Kushan Empire in the 3rd century to the early 9th century. The Shahis are generally split up into two eras: the Buddhist Shahis and the Hindu Shahis, with the change-over thought to have occurred sometime around 870. The kingdom was known as the Kabul Shahan or Ratbelshahan from 565-670, when the capitals were located in Kapisa and Kabul, and later Udabhandapura, also known as Hund for its new capital." Answer:
Answer: 9th century

Question: Question: "What event happened four years before the Battle of the Zab in 750?" Context: "Around 746, Abu Muslim assumed leadership of the Hashimiyya in Khurasan. In 747, he successfully initiated an open revolt against Umayyad rule, which was carried out under the sign of the black flag. He soon established control of Khurasan, expelling its Umayyad governor, Nasr ibn Sayyar, and dispatched an army westwards. Kufa fell to the Hashimiyya in 749, the last Umayyad stronghold in Iraq, Wasit, was placed under siege, and in November of the same year Abu al-Abbas was recognized as the new caliph in the mosque at Kufa.[citation needed] At this point Marwan mobilized his troops from Harran and advanced toward Iraq. In January 750 the two forces met in the Battle of the Zab, and the Umayyads were defeated. Damascus fell to the Abbasids in April, and in August, Marwan was killed in Egypt." Answer:
Answer:
Abu Muslim assumed leadership of the Hashimiyya