QUES: 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.
Do you have any questions?
MY QUESTION: Why do cars have tires?

QUES: My parents, Kelly and Kelley, said that it was that time of year to take a family vacation. We've been to big ride parks that have hotels with large pools. This year my parents wanted to do something different. They wanted to take us all to Elk River Castle. After lots of planning we hit the road for our trip. My Brother Kelsey and I enjoyed the long car ride there. Once we arrive, the castle looked much bigger than we had imagined. There was so much to see and so much to do. There was a swimming pool, movie theater and an elevator to take us from floor to floor. What a magical place! I was so excited because we had the whole place to our family! We spent our vacation playing around the huge castle and finding small mysterious places. There was even a tiny room in the back of one of the closets. My brother, Kelsey, and I played hide and go seek for hours, watched movies and swam until the sun went down. It was sad when our vacation finally came to an end but we made some amazing memories. We'll never forget our trip to Elk River Castle!
Do you have any questions?
MY QUESTION: Whose idea was it to go to Elk River Castle?

QUES: According to the radar reconstruction, American 77 reemerged as a primary target on Indianapolis Center radar scopes at 9:05, east of its last known position. The target remained in Indianapolis Center's airspace for another six minutes, then crossed into the western portion of Washington Center's airspace at 9:10. As Indianapolis Center continued searching for the aircraft, two managers and the controller responsible for American 77 looked to the west and southwest along the flight's projected path, not east-where the aircraft was now heading. Managers did not instruct other controllers at Indianapolis Center to turn on their primary radar coverage to join in the search for American 77. In sum, Indianapolis Center never saw Flight 77 turn around. By the time it reappeared in primary radar coverage, controllers had either stopped looking for the aircraft because they thought it had crashed or were looking toward the west. Although the Command Center learned Flight 77 was missing, neither it nor FAA headquarters issued an all points bulletin to surrounding centers to search for primary radar targets. American 77 traveled undetected for 36 minutes on a course heading due east for Washington, D.C. By 9:25, FAA's Herndon Command Center and FAA headquarters knew two aircraft had crashed into the World Trade Center. They knew American 77 was lost. At least some FAA officials in Boston Center and the New England Region knew that a hijacker on board American 11 had said "we have some planes." Concerns over the safety of other aircraft began to mount. A manager at the Herndon Command Center asked FAA headquarters if they wanted to order a "nationwide ground stop." While this was being discussed by executives at FAA headquarters, the Command Center ordered one at 9:25. The Command Center kept looking for American 77. At 9:21, it advised the Dulles terminal control facility, and Dulles urged its controllers to look for primary targets. At 9:32, they found one. Several of the Dulles controllers "observed a primary radar target tracking eastbound at a high rate of speed" and notified Reagan National Airport. FAA personnel at both Reagan National and Dulles airports notified the Secret Service.
Do you have any questions?
MY QUESTION: What was ordered at the Command Center at 9:25?

QUES: Dubai's Crown Prince Sheikh Mohamed Bin Rashid Al Maktoum inaugurated a free zone for e-commerce today, called Dubai Internet City. The preliminary stages of the project, the only one of its kind according to its designers, are estimated at $200 million. Sheikh Mohamed, who is also the Defense Minister of the United Arab Emirates, announced at the inauguration ceremony that "we want to make Dubai a new trading center." The minister, who has his own website, also said: "I want Dubai to be the best place in the world for state-of-the-art technology companies." He said companies engaged in e-commerce would be able to set up offices, employ staff and own equipment in the open zone, including fully-owned foreign companies. The e-commerce free zone is situated in north Dubai, near the industrial free zone in Jebel Ali, the top regional and tenth international leading area in container transit. The inauguration of Dubai Internet City coincides with the opening of an annual IT show in Dubai, the Gulf Information Technology Exhibition (Gitex), the biggest in the Middle East.
Do you have any questions?
MY QUESTION:
Which two other things does Dubai already stand out for?