QUES: There are many important organozinc compounds. Organozinc chemistry is the science of organozinc compounds describing their physical properties, synthesis and reactions. Among important applications is the Frankland-Duppa Reaction in which an oxalate ester(ROCOCOOR) reacts with an alkyl halide R'X, zinc and hydrochloric acid to the α-hydroxycarboxylic esters RR'COHCOOR, the Reformatskii reaction which converts α-halo-esters and aldehydes to β-hydroxy-esters, the Simmons–Smith reaction in which the carbenoid (iodomethyl)zinc iodide reacts with alkene(or alkyne) and converts them to cyclopropane, the Addition reaction of organozinc compounds to carbonyl compounds. The Barbier reaction (1899) is the zinc equivalent of the magnesium Grignard reaction and is better of the two. In presence of just about any water the formation of the organomagnesium halide will fail, whereas the Barbier reaction can even take place in water. On the downside organozincs are much less nucleophilic than Grignards, are expensive and difficult to handle. Commercially available diorganozinc compounds are dimethylzinc, diethylzinc and diphenylzinc. In one study the active organozinc compound is obtained from much cheaper organobromine precursors:

What are dimethylzinc, dietylzinc and diphenylzinc no longer allowed as?
What is the answer?
ANS: unanswerable
QUES: In Asia, various Chinese dynasties and Japanese shogunates controlled the Asian sphere. In Japan, the Edo period from 1600 to 1868 is also referred to as the early modern period. And in Korea, from the rising of Joseon Dynasty to the enthronement of King Gojong is referred to as the early modern period. In the Americas, Native Americans had built a large and varied civilization, including the Aztec Empire and alliance, the Inca civilization, the Mayan Empire and cities, and the Chibcha Confederation. In the west, the European kingdoms and movements were in a movement of reformation and expansion. Russia reached the Pacific coast in 1647 and consolidated its control over the Russian Far East in the 19th century.

Who controlled the Asian Sphere during the period between 1600-1868?
What is the answer?
ANS: Chinese dynasties and Japanese shogunates
QUES: METRO began light rail service on January 1, 2004, with the inaugural track ("Red Line") running about 8 miles (13 km) from the University of Houston–Downtown (UHD), which traverses through the Texas Medical Center and terminates at NRG Park. METRO is currently in the design phase of a 10-year expansion plan that will add five more lines. and expand the current Red Line. Amtrak, the national passenger rail system, provides service three times a week to Houston via the Sunset Limited (Los Angeles–New Orleans), which stops at a train station on the north side of the downtown area. The station saw 14,891 boardings and alightings in fiscal year 2008. In 2012, there was a 25 percent increase in ridership to 20,327 passengers embarking from the Houston Amtrak station.

 Where did the Blue Line rail track terminate?
What is the answer?
ANS:
unanswerable