Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Context: Assume that a school bus, like the one in Figure 12.2, passes by as you stand on the sidewalk. Its obvious to you that the bus is moving. It is moving relative to you and the trees across the street. But what about to the children inside the bus? They arent moving relative to each other. If they look only at the other children sitting near them, they will not appear to be moving. They may only be able to tell that the bus is moving by looking out the window and seeing you and the trees whizzing by. This example shows that how we perceive motion depends on our frame of reference. Frame of reference refers to something that is not moving with respect to an observer that can be used to detect motion. For the children on the bus, if they use other children riding the bus as their frame of reference, they do not appear to be moving. But if they use objects outside the bus as their frame of reference, they can tell they are moving. What is your frame of reference if you are standing on the sidewalk and see the bus go by? How can you tell the bus is moving? The video at the URL below illustrates other examples of how frame of reference is related to motion. MEDIA Click image to the left or use the URL below. URL: Did you ever go to a track meet like the one pictured in Figure 12.3? Running events in track include 100-meter sprints and 2000-meter races. Races are named for their distance. Distance is the length of the route between two points. The length of the route in a race is the distance between the starting and finishing lines. In a 100-meter sprint, for example, the distance is 100 meters. The SI unit for distance is the meter (1 m = 3.28 ft). Short distances may be measured in centimeters (1 cm = 0.01 m). Long distances may be measured in kilometers (1 km = 1000 m). For example, you might measure the distance a frogs tongue moves in centimeters and the distance a cheetah moves in kilometers. Maps can often be used to measure distance. Look at the map in Figure 12.4. Find Mias house and the school. You can use the map key to directly measure the distance between these two points. The distance is 2 kilometers. Measure it yourself to see if you agree. Things dont always move in straight lines like the route from Mias house to the school. Sometimes they change direction as they move. For example, the route from Mias house to the post office changes from west to north at the school (see Figure 12.4). To find the total distance of a route that changes direction, you must add up the distances traveled in each direction. From Mias house to the school, for example, the distance is 2 kilometers. From the school to the post office, the distance is 1 kilometer. Therefore, the total distance from Mias house to the post office is 3 kilometers. You Try It! Problem: What is the distance from the post office to the park in Figure 12.4? Direction is just as important as distance in describing motion. For example, if Mia told a friend how to reach the post office from her house, she couldnt just say, "go 3 kilometers." The friend might end up at the park instead of the post office. Mia would have to be more specific. She could say, "go west for 2 kilometers and then go north for 1 kilometer." When both distance and direction are considered, motion is a vector. A vector is a quantity that includes both size and direction. A vector is represented by an arrow. The length of the arrow represents distance. The way the arrow points shows direction. The red arrows in Figure 12.4 are vectors for Mias route to the school and post office. If you want to learn more about vectors, watch the videos at these URLs: (5:27) MEDIA Click image to the left or use the URL below. URL: You Try It! Problem: Draw vectors to 
 Question: change in position
motion

Context: In a New York City residence, Pierre Delacroix (Damon Wayans) rises to begin his daily routine. Brushing his teeth, he gives us by voice over a definition of satire. He tells us that with the rise of the Internet, video and interactive games, his field as a television writer has seen a drop in popularity. Meanwhile, in a dilapidated building, squatter Womack (Tommy Davidson) wakes up his friend Manray (Savion Glover) for a day of work. This consists of travelling to the CNS (Continental Network System) building where Delacroix works, and Manray tap dancing to entertain the workers. They then collect money from the workers. The men see Delacroix walk by, and ask him for monetary help in the form of work of some kind.Delacroix walks into a staff meeting late and is immediately castigated by his boss, Thomas Dunwitty (Michael Rapaport). Dunwitty informs the staff that CNS has poor ratings. He says he wants them to write funnier material, and ends the meeting. In the privacy of his office, Dunwitty tells Delacroix that the material Delacroix's been writing for him seems like it's about white people with black faces. Dunwitty asserts that Delacroix is an "oreo" with his Harvard education, because he won't write a "n----r show."The next day, Delacroix and his assistant Sloan Hopkins (Jada Pinkett Smith) talk. They've decided that Manray is the solution to his problem. Delacroix plans to write a show that will be so "offensive and racist," it will prove his point that the network only wants to see black buffoons on the air. Delacroix simply hopes to be fired, so he can be let go of his contract with CNS. Manray and Womack ask at the receptionist's desk for a "Delapoint" and the men working there tell them to step outside. However, Sloan steps into the lobby, sees what's happening, and escorts Manray and Womack to Delacroix's office. Delacroix explains to them that he has an idea for a television pilot, and they can make money with it. His main request is that Manray changes his name to Mantan, in an apparent homage to black character actor Mantan Moreland.On Sloan's walk home, she runs into her big brother Big Blak Afrika F/K/A Julius (Yasiin Bey). In Sloan's apartment, Julius and Sloan argue about his values, and he tells her to introduce him and his political hip-hop crew, the Mau Maus, to Delacroix.Delacroix has another meeting with Dunwitty. Delacroix proposes that the network start a variety show called "Mantan: The New Millenium Minstrel Show." Delacroix says that new faces are needed for the show, and has Sloan bring in Manray and Womack. The two men, respectively renamed "Mantan" and "Sleep'n Eat," will exhibit a range of stereotypical traits, Delacroix explains. Sloan is opposed to the proceedings, and suggests that there will be protest of the show they are planning. To seal the package, Manray dances atop a table in front of Dunwitty -- who immediately leaves to try to sell the show's concept to his executive bosses.Delacroix, Sloan and another woman hold auditions for the show. The first group of people (The Roots) audition to be the show's house band, The Alabama Porch Monkeys. After they perform, a dancer, a vulgar man shouting "I be smackin' my hoes," and a didgeridoo player all audition. The next hopeful is Honeycutt (Thomas Jefferson Byrd), an actor who bungles Shakespearean quotes and proclaims "N----s is a beautiful thing." Sloan's brother's group, the Mau Maus then do a fiery, confrontational performance; Pierre states via voice over that there is no place for them in his plan.Delacroix looks over a revised script for the show and confronts Dunwitty and his co-writer, Jukka about their alterations to it that even he finds racially offensive. Delacroix says that he won't be responsible for their changes, which Dunwitty says are to make the show funnier. Dunwitty says he knows black people better than Delacroix does, telling him, "Look 
 Question: The jokes and puns are extremely what?
racist

Context: Methicillin-resistant Staphylococcus aureus (MRSA) infections pose a major challenge in health care, yet the limited heterogeneity within this group hinders molecular investigations of related outbreaks. Pulsed-field gel electrophoresis (PFGE) has been the gold standard approach but is impractical for many clinical laboratories and is often replaced with PCR-based methods. Regardless, both approaches can prove problematic for identifying subclonal outbreaks. Here, we explore the use of whole-genome sequencing for clinical laboratory investigations of MRSA molecular epidemiology. We examine the relationships of 44 MRSA isolates collected over a period of 3 years by using whole-genome sequencing and two PCR-based methods, multilocus variable-number tandem-repeat analysis (MLVA) and spa typing. We find that MLVA offers higher resolution than spa typing, as it resolved 17 versus 12 discrete isolate groups, respectively. In contrast, whole-genome sequencing reproducibly cataloged genomic variants (131,424 different single nucleotide polymorphisms and indels across the strain collection) that uniquely identified each MRSA clone, recapitulating those groups but enabling higher-resolution phylogenetic inferences of the epidemiological relationships. Importantly, whole-genome sequencing detected a significant number of variants, thereby distinguishing between groups that were considered identical by both spa typing (minimum, 1,124 polymorphisms) and MLVA (minimum, 193 polymorphisms); this suggests that these more conventional approaches can lead to false-positive identification of outbreaks due to inappropriate grouping of genetically distinct strains. An analysis of the distribution of variants across the MRSA genome reveals 47 mutational hot spots (comprising 2.5% of the genome) that account for 23.5% of the observed polymorphisms, and the use of this selected data set successfully recapitulates most epidemiological relationships in this pathogen group. 
 Question: What is MRSA?

mrsa