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.

[Q]: 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.
[A]: Who attacks someone, causing the group to split up?

[Q]: Passage: The two main requirements of an anti-torque system are that it should prevent rotation of the sonde, and it should allow easy movement of the drill up and down the borehole. Attempts have been made to design drills with counter-rotating components so that overall torque is minimized, but these have had limited success. Five kinds of anti-torque systems have been devised for use with cable-suspended EM drills, though not all are in current use, and some drills have used a combination of more than one design. The first drill to require an anti-torque system was used at Camp Century by CRREL in 1966; the drill incorporated a set of hinged friction blades that swung out from the sonde when the drill motor was started. These were found to have very weak friction against the borehole wall, and were ineffective; the drill had to be controlled carefully to prevent twisting the cable. No other drills have attempted to use this approach.For the next deployment of the drill leaf springs were installed, and this has proved to be a more durable design. These are mounted vertically, with a curve outwards so that they are easily compressed by the borehole wall, and can slide up and down with the movement of the drill. They pass easily through any areas of irregularity in the borehole, but the edges of the springs cut into the borehole wall and prevent rotation. Leaf springs are very simple mechanically, with the additional benefit of being easy to adjust by changing the spacing between the end points. They can be placed anywhere on the drill that does not rotate, so they do not add length to the sonde. The shape is usually a fourth-order parabola, since this has been determined to provide the most even loading against the borehole wall. Leaf springs have been found to be so effective that they can prevent rotation even in heavy drills running at full power.Skate antitorque systems have blades attached to vertical bars which are pushed against the borehole wall; the blades dig into the wall and provide the anti-torque. Skates can be built with springs which allow them to keep the blades pressed against the wall in an irregular borehole, and to prevent problems in narrower parts of the borehole. Although skates are a popular design for anti-torque and have been used with success, they have difficulty preventing rotation in firn and at boundaries between layers of different densities, and can cause problems when drilling with high torque. When they fail, they act as reamers, removing chips from the wall which can fall to the drillbit and interfere with drilling.
[A]: What acts as reamers when they fail?

[Q]: Passage: With 2008's obZen, Meshuggah moved away from the experimentation of 2002's Nothing and 2005's Catch Thirtythree to return to the musical style of its previous albums, such as Contradictions Collapse, Destroy Erase Improve and Chaosphere, while still maintaining its focus on musical and technical innovation. The album loses some of the mathematical-like rhythmal quick changes of past releases and the melodic orchestration of Catch Thirty-Three and uses "angular" riffs, mid-tempo and common 4/4 beats. The album is a culmination of the band's previous work. Meshuggah decided to self-produce because it sought to retain artistic control over the recording and mixing process.For obZen, Haake returned to the drum kit most notably with his performance on the song "Bleed". In an interview for Gravemusic.com, Haake stated, "['Bleed'] was a big effort for me to learn, I had to find a totally new approach to playing the double bass drums to be able to do that stuff. I had never really done anything like that before like the fast bursts that go all the way through the song basically. So I actually spent as much time practicing that track alone as I did with all of the other tracks combined. It's kind of a big feat to change your approach like that and I'm glad we were able to nail it for the album. For a while though we didn't even know if it was going to make it to the album." Hagstrom also stated, "obZen is one of the most highly technical offerings the band has ever put to tape". Revolver Magazine confirms this statement: "At first listen, obZen seems less challenging to the listener than some of the band's other records, and most of the songs flow smoothly from one syncopated passage to the next. However, careful examination reveals that the material is some of the group's most complicated".
[A]:
What is the name of the album that loses some of the mathematical-like rhythmal quick changes of past releases?