Problem: Rough surfaces create more friction than smooth surfaces. Thats why cars have tires. Its also why we use rubber mats in areas that might get wet. In your bathtub, you may even use No-Slip tape. No-slip is another way of saying the items has a lot of friction. In Figure 1.9, the blades of the skates are very smooth. Thats why you cant slide across ice with shoes. The soles of your shoes are much rougher than skates. The rougher surface of shoes causes more friction and slows you down. Heavier objects also have more friction. A heavy object presses down with more force. The surfaces are held together more tightly. This makes the surfaces harder to slide past each other. Did you ever try to push something heavy across the floor? Heavy objects are much harder to push than light objects.

Question: "What is harder to do when surfaces are held together more tightly?"

Answer: "Surfaces harder to slide past each other"
Answer: yes

Problem: On a day it celebrated 50 years of giving free legal advice, Southern Arizona Legal Aid announced it has received two grants totaling more than $7 million. One of the grants includes the creation of a Web site with legal advice for the poor. A three-year grant worth $6.6 million and a separate technology grant were announced at a press conference and dinner held Thursday at Evo. A. DeConcini Federal Courthouse, 405 W. Congress St. Deconcini was one of the organization's early board members. Thursday's celebration was the first public even held at the courthouse. About 100 members of the legal community attended, including state Attorney General Janet Napolitano and Arizona Supreme Court Justice Thomas Zlaket. Both grants come from the Legal Services., a private, nonprofit corporation established by Congress in 1974 to offer poor people equal access to the justice system. It's funded through congressional appropriation. The $6.6 million grant will pay for staffing operations. The Web site, which will be created with a $50,000 grant, is intended to offer legal advice to poor people across Arizona, said Paul Julian, chief executive officer of Southern Arizona Legal Aid. He said he wants every poor person in Arizona to have legal help. "This is another step in trying to realize that. We feel like we do a pretty good job of helping people who find us," Julian said. Julian said that though most people do not own computers, they can still access them at libraries, schools, and courthouses. He said the Web site will help bridge the "digital divide" that keeps the poor from using the Internet as a resource. Southern Arizona Legal Aid was founded in 1951 as the Legal Aid Society of the Pima County Bar Association. It offered free legal advice on civil matters including disputes in small claims court, divorce proceedings and obtaining Social Security benefits. Charles Ares, a member of the board of directors in the 1950s, said the office was kind of a charity operation.

Question: "Who will the Web site benefit?"

Answer: "$2 million used for services"
Answer: no

Problem: Military Notification and Response. Boston Center did not follow the protocol in seeking military assistance through the prescribed chain of command. In addition to notifications within the FAA, Boston Center took the initiative, at 8:34, to contact the military through the FAA's Cape Cod facility. The center also tried to contact a former alert site in Atlantic City, unaware it had been phased out. At 8:37:52, Boston Center reached NEADS. This was the first notification received by the military-at any level-that American 11 had been hijacked: FAA: Hi. Boston Center TMU [Traffic Management Unit], we have a problem here. We have a hijacked aircraft headed towards New York, and we need you guys to, we need someone to scramble some F-16s or something up there, help us out. NEADS: Is this real-world or exercise? FAA: No, this is not an exercise, not a test. NEADS ordered to battle stations the two F-15 alert aircraft at Otis Air Force Base in Falmouth, Massachusetts, 153 miles away from New York City. The air defense of America began with this call. At NEADS, the report of the hijacking was relayed immediately to Battle Commander Colonel Robert Marr. After ordering the Otis fighters to battle stations, Colonel Marr phoned Major General Larry Arnold, commanding general of the First Air Force and NORAD's Continental Region. Marr sought authorization to scramble the Otis fighters. General Arnold later recalled instructing Marr to "go ahead and scramble them, and we'll get authorities later." General Arnold then called NORAD headquarters to report. F-15 fighters were scrambled at 8:46 from Otis Air Force Base.

Question: "How many military facilities did Boston Center try to contact?"

Answer: "3"
Answer:
no