Extract the answer to the question from the following context. Question: Who ruled the kind of government that existed during Cristina's regency? Context: During the regency of Maria Cristina, Espartero ruled Spain for two years as its 18th Prime Minister from 16 September 1840 to 21 May 1841. Under his progressive government the old regime was tenuously reconciled to his liberal policies. During this period of upheaval in the provinces he declared that all the estates of the Church, its congregations, and its religious orders were national propertythough in Valencia, most of this property was subsequently acquired by the local bourgeoisie. City life in Valencia carried on in a revolutionary climate, with frequent clashes between liberals and republicans, and the constant threat of reprisals by the Carlist troops of General Cabrera.
Ans: Prime Minister

Extract the answer to the question from the following context. Question: How does DNA and RNA contact? Context: Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.
Ans: polymerase binding site

Extract the answer to the question from the following context. Question: What reaction is not said to be a more useful option when compared to another one? Context: 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 -hydroxycarboxylic esters RR'COHCOOR, the Reformatskii reaction which converts -halo-esters and aldehydes to -hydroxy-esters, the SimmonsSmith 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:
Ans: Grignard

Extract the answer to the question from the following context. Question: What government sanctioned factor made the new migration of Blacks feel excluded? Context: Detroit remains one of the most racially segregated cities in the United States. From the 1940s to the 1970s a second wave of Blacks moved to Detroit to escape Jim Crow laws in the south and find jobs. However, they soon found themselves excluded from white areas of the citythrough violence, laws, and economic discrimination (e.g., redlining). White residents attacked black homes: breaking windows, starting fires, and exploding bombs. The pattern of segregation was later magnified by white migration to the suburbs. One of the implications of racial segregation, which correlates with class segregation, may be overall worse health for some populations.
Ans: laws