Problem: Earths magnetic field helps protect Earth and its organisms. It protects us from harmful particles given off by the sun. Most of the particles are attracted to the north and south magnetic poles. This is where Earths magnetic field is strongest. This is also where relatively few organisms live. Another benefit of Earths magnetic field is its use for navigation. People use compasses to detect Earths magnetic north pole. Knowing this helps them tell direction. Many animals have natural 'compasses' that work just as well. Birds like the garden warbler in Figure 1.36 use Earths magnetic field. They use it to guide their annual migrations. Recent research suggests that warblers and other migrating birds have structures in their eyes. These structures let them see Earths magnetic field as a visual pattern. 

Question: "Where is the structure located, that warblers use to detect the magnetic fields of Earth?"

Answer: "Tongue"
Answer: no

Problem: In February 1998, the 40-year-old Saudi exile Usama  Bin Laden and a fugitive Egyptian physician, Ayman al Zawahiri, arranged from their Afghan headquarters for an Arabic newspaper in London to publish what they termed a fatwa issued in the name of a "World Islamic Front." A fatwa is normally an interpretation of Islamic law by a respected Islamic authority, but neither  Bin Laden, Zawahiri, nor the three others who signed this statement were scholars of Islamic law. Claiming that America had declared war against God and his messenger, they called for the murder of any American, anywhere on earth, as the "individual duty for every Muslim who can do it in any country in which it is possible to do it." Three months later, when interviewed in Afghanistan by ABC-TV,  Bin Laden enlarged on these themes. He claimed it was more important for Muslims to kill Americans than to kill other infidels." It is far better for anyone to kill a single American soldier than to squander his efforts on other activities," he said. Asked whether he approved of terrorism and of attacks on civilians, he replied:"We believe that the worst thieves in the world today and the worst terrorists are the Americans. Nothing could stop you except perhaps retaliation in kind. We do not have to differentiate between military or civilian. As far as we are concerned, they are all targets." Note: Islamic names often do not follow the Western practice of the consistent use of surnames. Given the variety of names we mention, we chose to refer to individuals by the last word in the names by which they are known: Nawaf al Hazmi as Hazmi, for instance, omitting the article "al" that would be part of their name in their own societies. We generally make an exception for the more familiar English usage of "Bin" as part of a last name, as in  Bin Laden. Further, there is no universally accepted way to transliterate Arabic words and names into English. We have relied on a mix of common sense, the sound of the name in Arabic, and common usage in source materials, the press, or government documents. When we quote from a source document, we use its transliteration, e.g.,"al Qida" instead of al Qaeda. Though novel for its open endorsement of indiscriminate killing,  Bin Laden's 1998 declaration was only the latest in the long series of his public and private calls since 1992 that singled out the United States for attack. In August 1996,  Bin Laden had issued his own self-styled fatwa calling on Muslims to drive American soldiers out of Saudi Arabia. 

Question: "The fatwa that  Bin Laden and Ayman al Zawahiri arranged to published, what was the matter with it?"

Answer: "Fatwas are usually issued by a respected Islamic authority, which they were not"
Answer: yes

Problem: Not until 1998 did al Qaeda undertake a major terrorist operation of its own, in large part because  Bin Laden lost his base in Sudan. Ever since the Islamist regime came to power in Khartoum, the United States and other Western governments had pressed it to stop providing a haven for terrorist organizations. Other governments in the region, such as those of Egypt, Syria, Jordan, and even Libya, which were targets of some of these groups, added their own pressure. At the same time, the Sudanese regime began to change. Though Turabi had been its inspirational leader, General Omar al Bashir, president since 1989, had never been entirely under his thumb. Thus as outside pressures mounted, Bashir's supporters began to displace those of Turabi. The attempted assassination in Ethiopia of Egyptian President Hosni Mubarak in June 1995 appears to have been a tipping point. The would-be killers, who came from the Egyptian Islamic Group, had been sheltered in Sudan and helped by  Bin Laden. When the Sudanese refused to hand over three individuals identified as involved in the assassination plot, the UN Security Council passed a resolution criticizing their inaction and eventually sanctioned Khartoum in April 1996. A clear signal to  Bin Laden that his days in Sudan were numbered came when the government advised him that it intended to yield to Libya's demands to stop giving sanctuary to its enemies.  Bin Laden had to tell the Libyans who had been part of his Islamic army that he could no longer protect them and that they had to leave the country. Outraged, several Libyan members of al Qaeda and the Islamic Army Shura renounced all connections with him.  Bin Laden also began to have serious money problems. International pressure on Sudan, together with strains in the world economy, hurt Sudan's currency. Some of  Bin Laden's companies ran short of funds. As Sudanese authorities became less obliging, normal costs of doing business increased. Saudi pressures on the  Bin Laden family also probably took some toll. In any case,  Bin Laden found it necessary both to cut back his spending and to control his outlays more closely. 

Question: "Which group plotted the assassination of Hosni Mubarak?"

Answer: "Sudan"
Answer:
no