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.

Passage: Curiously, it appears that the Greeks did not "breed" their slaves, at least during the Classical Era, though the proportion of houseborn slaves appears to have been rather large in Ptolemaic Egypt and in manumission inscriptions at Delphi. Sometimes the cause of this was natural; mines, for instance, were exclusively a male domain. On the other hand, there were many female domestic slaves. The example of African slaves in the American South on the other hand demonstrates that slave populations can multiply.Xenophon advised that male and female slaves should be lodged separately, that "nor children born and bred by our domestics without our knowledge and consentno unimportant matter, since, if the act of rearing children tends to make good servants still more loyally disposed, cohabiting but sharpens ingenuity for mischief in the bad." The explanation is perhaps economic; even a skilled slave was cheap, so it may have been cheaper to purchase a slave than to raise one. Additionally, childbirth placed the slave-mother's life at risk, and the baby was not guaranteed to survive to adulthood.Houseborn slaves (oikogeneis) often constituted a privileged class. They were, for example, entrusted to take the children to school; they were "pedagogues" in the first sense of the term. Some of them were the offspring of the master of the house, but in most cities, notably Athens, a child inherited the status of its mother.
What were entrusted to take children to school?

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.
What acts as reamers when they fail?

Passage: Anderson is a successful American hitman whose employer sends him to do a job in Argentina. His contacts inform him that his target is a former general who took part in Argentina's last military dictatorship. Following a meeting with one of the co-conspirators, Anderson hears music and is shown a tango studio. He is immediately entranced by the dancing and wants to learn more about it, which leads to his meeting with Manuela, a local tango dancer and instructor.
Things are not as easy as they seem. Anderson learns that the assassination job will be delayed, due to his target sustaining an injury in a riding accident. A paranoid Anderson simultaneously rents a room in two different hotels. From the safety but close proximity of one hotel room, he witnesses police converge on the other hotel. Anderson will fulfill his obligation to do the job despite the obvious reality that there is a leak. In the meantime, Anderson begins to immerse himself in the world of the tango, while balancing his plans to carry out the hit. The conspirator Miguel is harshly interrogated by Buenos Aires police. Miguel can eventually breathe a sigh of relief when his conspirator within the Argentinian federal authorities shows up. Anderson eventually makes it out of Argentina safely.
What was the profession of the person injured in a riding accident?