QUES: Density is also an important physical property of matter. The concept of density combines what we know about an objects mass and volume. Density reflects how closely packed the particles of matter are. When particles are packed together more tightly, matter is more dense. Differences in density of matter explain many phenomena. It explains why helium balloons rise. It explains why currents such as the Gulf Stream flow through the oceans. It explains why some things float in or sink. You can see this in action by pouring vegetable oil into water. You can see a colorful demonstration in this video.
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MY QUESTION: How can I observe the role density plays?

QUES: ATLANTA, Georgia (CNN) -- On a plot of soil, nestled against the backdrop of skyscrapers in downtown Atlanta, Georgia, a group of residents are turning a lack of access to fresh produce into a revival of old traditions and self-empowerment. Urban farming is a way for African-Americans to connect with the earth, says Cashawn Myers of HABESHA. HABESHA Gardens is one of many urban gardens sprouting up around the country. Fruits and vegetables are thriving in this community garden located in an economically depressed area of the city known as Mechanicsville. But the garden serves an even greater purpose. The harvest helps feed some of the neediest members of the neighborhood. "It's a reawakening going on. It's almost like it's a renaissance," says Cashawn Myers, director of HABESHA Inc. "There's a Ghanaian proverb that says Sankofa. Sankofa means return to your past so you can move forward. Even if you look at coming over here during our enslavement, we were brought here to cultivate the land because that's something we did on the continent. So really, that's what many of the people are doing now," he said. Myers believes urban farming is a way for many African-Americans to reconnect with their past. iReport.com: Show us your urban farm "They are going through a process of Sankofa and going to what they traditionally did, which is connect to the Earth so they can move forward and grow," he says. But HABESHA Gardens isn't unique. Former pro basketball player Will Allen, who is considered to be one of the nation's leading urban farmers and founder of Growing Power Inc., estimates that there are hundreds of thousands of urban gardens in inner cities across America. Urban farms help feed people, sustain neighorhoods " "It's beyond a movement at this point. Its more like a revolution," says Allen.
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MY QUESTION: What actions are a group of residents performing in an effort to connect African Americans with the earth?

QUES: The Reconquest: The aim of the Crusades in Spain was the eviction of the Muslims. After the recovery of Jerusalem in 1099, it took four hundred years of sieges and battles, treaties, betrayals, and yet more battles, before Christian kings and warlords succeeded in subduing the Moors. On 10 September 1229, a Catalan army led by King Jaume I of Aragon and Catalunya took the Mallorcan shore near the present-day resort of Santa Ponca. The defenders retreated inside the walls of Palma, but on the last day of 1229 the city fell, and pockets of resistance throughout the island were also defeated. Jaume I proved to be an enlightened ruler who profited from the talents of the Moorsconverted by force to Christianityas well as of the island's large Jewish and Genoese trading communities. Mallorca prospered. The Moors on Menorca speedily agreed to pay an annual tribute to Aragon and were left in peace. The island's tranquility lasted until 1287, when Alfonso III of Aragon, smarting over a series of humiliations at the hands of his nobles, found a pretext for invasion. The Moors were defeated and expelled or killed. In contrast to Mallorca, Menorca's economy was devastated for decades. Jaume I died after reigning in Aragon for six decades, but he made the cardinal error of dividing between his sons the lands he had fought for so long to unite. At first this resulted in an Independent Kingdom of Mallorca, under Jaume II, followed by Sanc and Jaume III. But family rivalry triggered the overthrow of Jaume III by his cousin Pedro IV, who then seized the Balearics for Aragon. Attempting a comeback, Jaume was killed in battle near Llucmajor in 1349. A newly unified Christian Spain under the Catholic Monarchs, Ferdinand and Isabella, completed the Reconquest, defeating the only Moorish enclave left on the Iberian peninsula, Granada, in 1492. However, the centralized kingdom failed to incorporate the Balearics politically or economically.
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MY QUESTION: Jaume was defeated by whom and died in what year?

QUES: Expansion quickly peaked however, and the European powers who had carved up the New World set about testing each other in dynastic conflicts and colonial rivalry. The English were the main rivals of the Dutch on the high seas, and there were several wars between the two in the 17th and 18th centuries. In 16651667 the Dutch sailed up the River Medway and sank the British fleet moored there. The 18th century saw Amsterdam grow into the foremost financial center in the world, but the seeds of decline had already been planted. When the English colonies in New England rose up in revolt against the British, they found ready Ailies in the Dutch. From their colonies in the Caribbean they sent caches of arms and ammunition. The British were furious and went to war in 1780, destroying the Dutch navy and signaling a sudden decline in power and influence from which the Netherlands never recovered. Trade suffered to such an extent that in 1791 the VOC went into liquidation. In the latter part of the century there were anti-Orange demonstrations by pro-French factions in the country, and in 1795 Napoleon Bonaparte took the Netherlands in his epic march across Europe. Under the yoke of another foreign power, and with trade at an all time low, the Golden Age was truly dead. The Return of the House of Orange Napoleon installed his brother Louis as King of Holland and he chose to take the fine Town Hall on Dam Square as his palacenow the Koninklijk Palace. But only four years later he fled the city after civil disturbances broke out when he raised taxes. When Napoleon's bubble burst and French power began to wane, William of Orange emerged from exile and was proclaimed king in 1813. Amsterdam had to work its way out of economic decline, but throughout the 19th century the city grew steadily. Industrialization changed the city. With the building of the Central Station at the end of the century, Amsterdam turned its back on its seafaring past and looked towards the mechanical age for its future. The station was built over the old harbor wall and some of the oldest canals in the city center were filled in to allow better access to motorized vehicles. Dam Square was landlocked for the first time in its history.
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MY QUESTION:
Who sent caches of arms and ammunition to the English colonies?