This task is about creating an unanswerable question based on a given passage. Construct a question that looks relevant to the given context but is unanswerable. Following are a few suggestions about how to create unanswerable questions:
(i) create questions which require satisfying a constraint that is not mentioned in the passage
(ii) create questions which require information beyond what is provided in the passage in order to answer
(iii) replace an existing entity, number, date mentioned in the passage with other entity, number, date and use it in the question
(iv) create a question which is answerable from the passage and then replace one or two words by their antonyms or insert/remove negation words to make it unanswerable.
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Question: Passage: During the early 20th century, northerners were attracted to the city, and Miami prospered during the 1920s with an increase in population and infrastructure. The legacy of Jim Crow was embedded in these developments. Miami's chief of police, H. Leslie Quigg, did not hide the fact that he, like many other white Miami police officers, was a member of the Ku Klux Klan. Unsurprisingly, these officers enforced social codes far beyond the written law. Quigg, for example, "personally and publicly beat a colored bellboy to death for speaking directly to a white woman."

Answer: Who was a unnotable chief of the Miami police?


Question: Passage: There has, however, been interest among railroad operators in returning to DC use at higher voltages than previously used. At the same voltage, DC often has less loss than AC, and for this reason high-voltage direct current is already used on some bulk power transmission lines. DC avoids the electromagnetic radiation inherent with AC, and on a railway this also reduces interference with signalling and communications and mitigates hypothetical EMF risks. DC also avoids the power factor problems of AC. Of particular interest to railroading is that DC can supply constant power with a single ungrounded wire. Constant power with AC requires three-phase transmission with at least two ungrounded wires. Another important consideration is that mains-frequency 3-phase AC must be carefully planned to avoid unbalanced phase loads. Parts of the system are supplied from different phases on the assumption that the total loads of the 3 phases will even out. At the phase break points between regions supplied from different phases, long insulated supply breaks are required to avoid them being shorted by rolling stock using more than one pantograph at a time. A few railroads have tried 3-phase but its substantial complexity has made single-phase standard practice despite the interruption in power flow that occurs twice every cycle. An experimental 6 kV DC railway was built in the Soviet Union.

Answer: Railroad operators have shown little interest in returning to what?


Question: Passage: Although less common than in earlier periods, in modern times, formal charges of heresy within Christian churches still occur. Issues in the Protestant churches have included modern biblical criticism and the nature of God. In the Catholic Church, the Congregation for the Doctrine of the Faith criticizes writings for "ambiguities and errors" without using the word "heresy".

Answer:
What charge is just as common in modern times?