QUES: If you have a mass of 50 kg on Earth, what is your weight in newtons? An object with more mass is pulled by gravity with greater force. Mass and weight are closely related. However, the weight of an object can change if the force of gravity changes. On Earth, the force of gravity is the same everywhere. So how does the force of gravity change? It doesnt if you stay on Earth. What if we travel to another planet or moon in our solar system? Look at the photo of astronaut Edwin E. Aldrin Jr. taken by fellow astronaut Neil Armstrong in the Figure. They were the first humans to walk on the moon. An astronaut weighs less on the moon than he would on Earth. This is because the moons gravity is weaker than Earths. The astronauts mass, on the other hand, did not change. He still contained the same amount of matter on the moon as he did on Earth. If the astronaut weighed 175 pounds on Earth, he would have weighed only 29 pounds on the moon. If his mass on Earth was 80 kg, what would his mass have been on the moon? [Figure 3]
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MY QUESTION: How does gravity change?

QUES: Dam Good Luck: From the beginning, Las Vegas was built to serve travelers. The railroad needed a way station, and Las Vegas was the place. Growth continued for ten years, and by 1915 the town had telephones, round-the-clock electricity, and a growing populationmany of whom worked in the railroad repair shop. But such heady progress would soon come to a halt. The growing competition in rail transport resulted in Union Pacific buying the Los AngelesSalt Lake line. Union Pacific then consolidated its operations, eliminating the Las Vegas repair facility. Additionally, Las Vegas had been made a part of Nevada's new Clark County in 1909, a year when the legislature also outlawed gambling. These unfortunate circumstances threatened to relegate Las Vegas to the status of a small desert community that could no longer support its 3000 residents. But the southwest's growing need for water, combined with Las Vegas's fortuitous proximity to the Colorado River, would give Las Vegas a second chance to achieve prosperity. Construction on Hoover Dam (originally Boulder Dam, subsequently renamed for the president who authorized the project) began in 1931 in a canyon 45 miles (72 km) southeast of Las Vegas. Providing an influx of $165 million to the southwestern economy, Hoover Dam played a major role in preventing Las Vegas from drying up, both financially and literally. Not only did it create jobs, but it also created Lake Mead, the massive reservoir that today provides water to all of southern Nevada. More Government Help: The construction of Hoover Dam did not single-handedly save Las Vegas, however. The state legislature helped as well, by legalizing gambling in 1931 and thus solidifying the future of the town, though legislators and residents could never have known this at the time. The hordes of people who attended Hoover Dam's 1935 dedication set the city's now-formidable public relations machine into action. They went to work on what has become one of the lengthiest citywide tourism campaigns ever attempted. It didn't take long for the city to establish itself as a wild-West town with an "anything goes" attitude. Vices outlawed or heavily controlled elsewhere were legal here, available any hour of any day (or night).
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MY QUESTION: What circumstances threatened to relegate Las Vegas to the status of a small desert community that could no longer support its 3000 residents?

QUES: When land is cleared, habitats are lost. It may be cleared for agriculture. It may also be used for building new homes or businesses. Within the past 100 years, the amount of land used for agriculture has almost doubled. Land used for grazing cattle has more than doubled. Many wetlands have also been lost to agriculture. The U.S. has lost almost all the natural tall-grass prairies. Thee areas of tall thick grass have virtually disappeared. These areas of land had thick fertile soil. Their grasses had very deep root systems. These deep and thick roots reduced the amount of soil erosion. They also were home to many plants and animals. Prairies were wonderful places. They were home to colorful flowers, prairie dogs, and herds of bison.
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MY QUESTION: What lived on prairies?

QUES: (CNN) -- Sevilla have sacked coach Manolo Jimenez after their disappointing home draw to bottom-club Xerez on Tuesday extended the club's winless run to seven games. Despite lying fifth in the Spanish Primera Liga table, Sevilla were knocked out of the lucrative European Champions League by Russian side CSKA Moscow last week. Jimenez had also secured a Copa del Rey final against Atletico Madrid but it wasn't enough to save the 46-year-old's job. The club's sporting director Ramon Rodriguez admitted the decision had been difficult but said he had "done what I had to." He told the club's official Web site: "It was an unavoidable situation and we had to find a solution, and the pain that it brings. "Tuesday was the end of the story but the decision comes from the image and dynamics of the team. Without doubt we are grateful to Manolo. He is an excellent professional, he has made all this possible and impossible. However it is obvious that he could not get a response out of the team. "Fortunately we believe that there is time. The growth and the ambition of the club is shown in the change of the manager. We are fighting for important things." Xerez's injury-time equaliser on Tuesday meant Sevilla's last league success was against Real Mallorca back in February. Ironically, it is Mallorca who occupy the much-coveted fourth spot in the table that guarantees Champions League football next season. Jimenez took charge in October 2007 when former coach Juande Ramos left to take over at English Premier League team Tottenham.
Do you have any questions?
MY QUESTION:
Why is Ramon Rodriguez grateful to Monolo Jimenez?