instruction:
This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
question:
An illustrative example of official involvement in organized crime can be found from 1920s and 1930s Shanghai, where Huang Jinrong was a police chief in the French concession, while simultaneously being a gang boss and co-operating with Du Yuesheng, the local gang ringleader. The relationship kept the flow of profits from the gang's gambling dens, prostitution, and protection rackets undisturbed.[citation needed]
answer:
When was Jinrong a police chief in this area?

question:
In cpDNA, there are several A G deamination gradients. DNA becomes susceptible to deamination events when it is single stranded. When replication forks form, the strand not being copied is single stranded, and thus at risk for A G deamination. Therefore, gradients in deamination indicate that replication forks were most likely present and the direction that they initially opened (the highest gradient is most likely nearest the start site because it was single stranded for the longest amount of time). This mechanism is still the leading theory today; however, a second theory suggests that most cpDNA is actually linear and replicates through homologous recombination. It further contends that only a minority of the genetic material is kept in circular chromosomes while the rest is in branched, linear, or other complex structures.
answer:
What kind of gradients does cpDNA have?

question:
Though much of Enlightenment political thought was dominated by social contract theorists, both David Hume and Adam Ferguson criticized this camp. Hume's essay Of the Original Contract argues that governments derived from consent are rarely seen, and civil government is grounded in a ruler's habitual authority and force. It is precisely because of the ruler's authority over-and-against the subject, that the subject tacitly consents; Hume says that the subjects would "never imagine that their consent made him sovereign", rather the authority did so. Similarly, Ferguson did not believe citizens built the state, rather polities grew out of social development. In his 1767 An Essay on the History of Civil Society, Ferguson uses the four stages of progress, a theory that was very popular in Scotland at the time, to explain how humans advance from a hunting and gathering society to a commercial and civil society without "signing" a social contract.
answer:
In what work did Ferguson explain how humans advanced from a hunting and gathering society to a commercial and civil society without "signing" a social contract?