In architecture Durer cites Vitruvius but elaborates his own classical designs and columns. In typography, Durer depicts the geometric construction of the Latin alphabet, relying on Italian precedent. However, his construction of the Gothic alphabet is based upon an entirely different modular system. The fourth book completes the progression of the first and second by moving to three-dimensional forms and the construction of polyhedra. Here Durer discusses the five Platonic solids, as well as seven Archimedean semi-regular solids, as well as several of his own invention. In all these, Durer shows the objects as nets. Finally, Durer discusses the Delian Problem and moves on to the 'construzione legittima', a method of depicting a cube in two dimensions through linear perspective. It was in Bologna that Durer was taught (possibly by Luca Pacioli or Bramante) the principles of linear perspective, and evidently became familiar with the 'costruzione legittima' in a written description of these principles found only, at this time, in the unpublished treatise of Piero della Francesca. He was also familiar with the 'abbreviated construction' as described by Alberti and the geometrical construction of shadows, a technique of Leonardo da Vinci. Although Durer made no innovations in these areas, he is notable as the first Northern European to treat matters of visual representation in a scientific way, and with understanding of Euclidean principles. In addition to these geometrical constructions, Durer discusses in this last book of Underweysung der Messung an assortment of mechanisms for drawing in perspective from models and provides woodcut illustrations of these methods that are often reproduced in discussions of perspective.

Question: "In which book does Durer show the understanding of Euclidean principles?"

Response: "His last book"

A: yes

Washington (CNN) -- The Pacific island nation of Palau has agreed to take in 17 Chinese Muslims held at the U.S. prison camp at Guantanamo Bay, Cuba, the country's ambassador to the United States said Wednesday. The map shows the Pacific island nation of Palau in relation to China. Details of the transfer are still being worked out, Ambassador Hersey Kyota told CNN. But Kyota said his country, a former U.S. Pacific trust territory, has agreed to take in the ethnic Uighur detainees "for humanitarian reasons" and because of the "special relationship" between Palau and the United States. U.S. State Department spokesman Ian Kelly would not comment on the announcement, telling reporters, "We're still involved in ongoing discussions." The agreement includes some U.S. aid for Palau, Kyota said, but he said those details remained to be worked out as well. The country, with a population of about 20,000, is about 1,000 miles southeast of Manila, Philippines, and about 4,600 miles west of Hawaii. Palau has received nearly $900 million in U.S. aid since independence in 1994, according to congressional auditors, and depends on Washington for defense. The "Compact of Free Association" between Palau and the United States is up for review, but Kelly said any additional aid offer "is not linked to any other discussions we may be having with the government of Palau." The Uighurs were accused of receiving weapons and military training in Afghanistan.

Question: "Where are the Uighur detainees currently held?"

Response: "Guantanamo Bay, Cuba"

A: yes

Fossils may form in other ways. Fossils can be preserved almost completely. In this process, the organism doesnt change much. As seen below, tree sap may cover an organism. With time, the sap hardens. It turns to into amber. The original organism is preserved. This is very exciting for scientists. They are able to study the DNA of the organism that no longer lives on Earth. Some animals have been found frozen in ice. Others have been found in tar pits after falling in. Molds and casts are another way organisms can be fossilized. Have you ever walked in soft mud and left footprints? Once in a while, these traces of organisms can be preserved. In this case, nothing is left of the organism. A mold is an imprint of an organism that is preserved in rock. The organisms remains break down completely. There is nothing left of the original plant and animal.

Question: "What are three materials an organism can be preserved in?"

Response: "Ice, amber, and tar"

A:
yes