In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
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Question: Passage: A man unveils a valuable painting he picked up for $50,000 and is killed. A card with a large black ace (of spades) is put on his chest. Another "Black Ace" victim. The killer sends his victims a Black Ace card, warning them they are to die and then kills them, his way of taunting the police. Neil Broderick, an author, intends writing a book about him and is on his way to see Thornton Drake to get more information about him. Austin Winters is his secretary and Neil met his daughter Martha on the train, on the way to Chicago.
Drake has just received a Black Ace, with the words: "At seven tomorrow night", the time he is to be killed. Two plainclothes cops arrive from police headquarters, having had a call, Clancy and Dugan (both incompetents). Martha suggests that they leave for Drake's Louisiana plantation tomorrow morning and be far away from there at seven tomorrow night. Drake agrees and suggests they all go. On the flight, the lights go off for some seconds and when they come on again, Austin Winters is dead without a mark on him.
At the plantation, Clancy ineptly questions the suspects till Neil points out that they are now in another state, so out of their jurisdiction. Neil goes to another room and makes a phone call, then signals to someone outside. After he finishes his call, the line is cut. Meanwhile one of the pilots has taken off in the plane, leaving the other pilot, Henderson, behind who claims he does not know anything though he was out of the cockpit when Winters was killed.
The coroner finds a letter on the dead man which is to be read if Winters dies. It will reveal the identity of the Black Ace. Clancy starts reading it aloud and unsurprisingly the lights go off and the letter has vanished when the lights are turned on again. People locked in their rooms that night and Neil has a hidden car outside signal to him.

Answer: Who is Neil Broderick writing a book about?


Question: Passage: Public transport in the city consists primarily of a First West of England bus network. Other providers are Abus, Stagecoach West, Stagecoach South West and Wessex Bus. Bristol's bus service has been criticised as unreliable and expensive, and in 2005 FirstGroup was fined for delays and safety violations.Although the city council has included a light rail system in its local transport plan since 2000, it has not yet funded the project; Bristol was offered European Union funding for the system, but the Department for Transport did not provide the required additional funding. The most recent light rail proposal was put forward as part of a consultation produced by the West of England Local Enterprise Partnership in November 2016, outlining potential light rail/tram routes from the city centre to Bristol Airport, the eastern and north west fringes of the city, and a route along the A4 road to Bath. In 2017, a further feasibility study will be undertaken into the possibility of an underground light rail system.A new bus rapid transit system (BRT) called MetroBus, is currently under construction across Bristol, as of 2018, to provide a faster and more reliable service than buses, improve transport infrastructure and reduce congestion. The MetroBus rapid transit scheme will run on both bus lanes and segregated guided busways on three routes; North Fringe to Hengrove (route m1), Ashton Vale to Bristol Temple Meads (route m2), and Emersons Green to The Centre (route m3). MetroBus services started in 2018.Three park and ride sites serve Bristol.
The city centre has water transport operated by Bristol Ferry Boats, Bristol Packet Boat Trips and Number Seven Boat Trips, providing leisure and commuter service in the harbour.

Answer: Number Seven Boat Trips operates water transport in what city?


Question: Passage: All of the surviving megalithic tombs from the Early Neolithic period have suffered from neglect and the ravages of agriculture. Although Ashbee noted that the Coldrum Stones represent "Kent's least damaged megalithic long barrow", it too has suffered considerable damage, having become dilapidated and fallen apart over the six millennia since its original construction. Most prominently, the eastern side has largely collapsed, with the stones that once helped to hold up the side of the barrow having fallen to the bottom of the slope. Conversely, it is possible that the sarsens at the bottom of the slope were not part of the original monument, but were stones found in nearby fields which were deposited there by farmers.Excavation of Chestnuts Long Barrow revealed that it had been systematically destroyed in one event, and Ashbee suggested that the same may have happened to the Coldrum Stones. He believed that the kerb-stones around the barrow were toppled, laid prostrate in the surrounding ditch, and then buried during the late 13th or early 14th century, by Christians seeking to obliterate non-Christian monuments. Conversely, the archaeologist John Alexander—who excavated Chestnuts in 1957—suggested that the Medway tombs were destroyed by robbers looking for treasure within them. As evidence, he pointed to the Close Roll of 1237, which ordered the opening of tumuli on the Isle of Wight in search for treasure, a practice which may have spread to Kent around the same time. Alexander believed that the destruction in Kent may have been brought about by a special commissioner, highlighting that the "expertness and thoroughness of the robbery" at Chestnuts would have necessitated resources beyond that which a local community could probably muster. Ashbee further suggested that in subsequent centuries, locals raided the damaged Coldrum tomb for loamy chalk and stone, which was then re-used as building material.

Answer:
What is the name of the work that Ashbee believes was destroyed by Christians in one event?