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: The estate's condition declined more during the 1910s. William de Bois Maclaren was a publisher and Scout Commissioner from Rosneath, Dumbartonshire, Scotland. During a business trip to London, Maclaren was saddened to see that Scouts in the East End had no suitable outdoor area to conduct their activities. He contacted Lord Robert Baden-Powell, who appointed P.B. Nevill to handle the matter. Nevill was Scout Commissioner of the East End.
On 20 November 1918 over dinner at Roland House, the Scout Hostel in Stepney, Maclaren agreed to donate £7,000 to the project. Part of the agreement included narrowing the areas to look for suitable land to Hainault Forest and Epping Forest. Rover Scouts searched both without success, but then John Gayfer, a young assistant Scoutmaster, suggested Gilwell Hall, a place he went bird-watching. Nevill visited the estate and was impressed, though the buildings were in poor condition. The estate was for sale for £7,000, the price Maclaren had donated. The estate totaled 21 hectares (52 acres) at the time.
The estate was purchased in early 1919 by Maclaren for the Boy Scout Association. Nevill first took his Rover Scouts to begin repairing the estate on Maundy Thursday, 17 April 1919. On this visit, the Rovers slept in the gardener's shed in the orchard because the ground was so wet they could not pitch tents. They called this shed "The Pigsty" and though dilapidated, it still stands, as it is the site of the first Scout campsite at Gilwell Park. Maclaren was a frequent visitor to Gilwell Park and helped repair the buildings. His dedication was so great that he donated another £3,000. Maclaren's interest had been in providing a campground, but Baden-Powell envisioned a training centre for Scouters.
An official opening was planned for 19 July 1919 but it was delayed until Saturday, 26 July 1919 so that Scouts could participate in the Official Peace Festival commemorating the end of World War I. Invitations were changed by hand to save money. Significant remodeling and construction was done in the 1920s. Because of limited finances, few improvements were made during the Great Depression of the 1930s.
Baden-Powell never lived at Gilwell Park but he often camped, lectured, taught courses, and attended meetings. He emphasized the importance of Scouters' training at Gilwell Park for Scouting by taking it as the territorial designation in his peerage title of 1st Baron Baden-Powell of Gilwell in 1929 when the barony was conferred upon him by the king.

Answer: What is the last name of the person who contacted Lord Robert Baden-Powell, who appointed P.B. Nevill to handle the matter involving a lack of suitable outdoor areas?


Question: Passage: Two days after the events of the first film, a traumatized and blood-covered Sarah escapes the cave with no memory of the events. She is taken to a hospital, where it is found that some of the blood on her belongs to Juno Kaplan. Sheriff Vaines takes his deputy Elen Rios, Sarah, and three spelunking specialists – Dan, Greg, and Cath – to the cave to find the missing women. The team members are sent down via an old mine shaft operated by the old, mysterious Ed Oswald.
The group discovers Rebecca's mutilated body, causing Sarah to have flashbacks of the crawlers and causing Vaines to believe Sarah may be responsible for the girls' disappearance.  While crawling through a tunnel, she attacks Vaines and the others, causing the others to split up. Vaines runs to search for Sarah, and in the process is surprised by a crawler, and fires his gun in a panic, causing a minor collapse in the cavern which traps Cath, separating her from Rios, Dan, and Greg.  The three decide to find an alternate way around in order to try to free Cath and arrive in a room full of bones, where they find Holly's video camera. They watch it and realize the women were attacked by the crawlers. The three are then themselves attacked by crawlers and separated.
Rios starts calling for help, alerting the crawlers to her location, but is rescued by Sarah.  The two then watch as a crawler kills Dan and drags his body away, prompting Sarah to inform Rios that the crawlers are blind and hunt via sound. After escaping from and killing a crawler, Cath finds Greg before the two escape from another crawler and find Sam's body. They decide to try to use her to swing across a chasm, but are attacked again. Greg sacrifices himself to buy time for Cath, but she ultimately does not survive.

Answer:
Who attacks someone, causing the group to split up?