QUES: 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.

Who was the Umayyad governor of Khurasan who was defeated by Abu Muslim?
What is the answer?
ANS: Nasr ibn Sayyar
QUES: The lower (Triassic) boundary is set by the PermianTriassic extinction event, during which approximately 90% to 96% of marine species and 70% of terrestrial vertebrates became extinct. It is also known as the "Great Dying" because it is considered the largest mass extinction in the Earth's history. The upper (Cretaceous) boundary is set at the CretaceousTertiary (KT) extinction event (now more accurately called the CretaceousPaleogene (or KPg) extinction event), which may have been caused by the impactor that created Chicxulub Crater on the Yucatan Peninsula. Towards the Late Cretaceous large volcanic eruptions are also believed to have contributed to the CretaceousPaleogene extinction event. Approximately 50% of all genera became extinct, including all of the non-avian dinosaurs.

What is the largest extinction of species in Earth's history known as?
What is the answer?
ANS: Great Dying
QUES: Resonant antennas are expected to be used around a particular resonant frequency; an antenna must therefore be built or ordered to match the frequency range of the intended application. A particular antenna design will present a particular feedpoint impedance. While this may affect the choice of an antenna, an antenna's impedance can also be adapted to the desired impedance level of a system using a matching network while maintaining the other characteristics (except for a possible loss of efficiency).

Which antenna type would be best for a project requiring a specific frequency?
What is the answer?
ANS:
Resonant antennas