The inhabited history of the Las Vegas Valley stretches to 23,000 b.c. , when much of the area was covered by a prehistoric lake. During this period, the indigenous people lived in caves, hunting the mammals that gathered at the shoreline. The landscape of the valley changed dramatically over the next 200 centuries. The glaciers feeding the lake melted away and the lake evaporated. Fossils tell an obscure story of man's slow and sporadic development. Around 3000 b.c. , native Archaic Indians began to develop a lasting hunting and gathering culture. By this time, the valley was in much the same geographic state as it exists in today, with one exceptionthe presence of artesian springs that bubbled to the surface in several areas. These springs fed a network of streams draining through the Las Vegas Wash to the Colorado River. The areas surrounding the springs were desert oases: sprawling collections of grasses, trees, and wildlife. Many springs lay in areas that would eventually become the center of the modern Las Vegas metropolis. For about 4000 years, the Archaics thrived in a culture that included many signs of early civilization. Signs of even more advancement appeared halfway through the first millennium a.d. , when the Anasazi Indians inhabited the valley. Far more progressive than the Archaics, the Anasazi utilized such formal agricultural techniques as irrigation to assist their harvest. This permitted the Anasazi to achieve a benchmark of advanced societythe ability to live in permanent shelters year-round without need to follow wildlife. Mysteriously, the Anasazi vanished from the valley around a.d.

Question: "How did the Archaic Indians survive?"

Answer: "Advanced agricultural techniques"

Response: no

Bin Laden reportedly discussed the planes operation with KSM and Atef in a series of meetings in the spring of 1999 at the al Matar complex near Kandahar. KSM's original concept of using one of the hijacked planes to make a media statement was scrapped, but Bin Laden considered the basic idea feasible. Bin Laden, Atef, and KSM developed an initial list of targets. These included the White House, the U.S. Capitol, the Pentagon, and the World Trade Center. According to KSM, Bin Laden wanted to destroy the White House and the Pentagon, KSM wanted to strike the World Trade Center, and all of them wanted to hit the Capitol. No one else was involved in the initial selection of targets. Bin Laden also soon selected four individuals to serve as suicide operatives: Khalid al Mihdhar, Nawaf al Hazmi, Khallad, and Abu Bara al Yemeni. During the al Matar meetings, Bin Laden told KSM that Mihdhar and Hazmi were so eager to participate in an operation against the United States that they had already obtained U.S. visas. KSM states that they had done so on their own after the suicide of their friend Azzam (Nashiri's cousin) in carrying out the Nairobi bombing. KSM had not met them. His only guidance from Bin Laden was that the two should eventually go to the United States for pilot training. Hazmi and Mihdhar were Saudi nationals, born in Mecca. Like the others in this initial group of selectees, they were already experienced mujahideen. They had traveled together to fight in Bosnia in a group that journeyed to the Balkans in 1995. By the time Hazmi and Mihdhar were assigned to the planes operation in early 1999, they had visited Afghanistan on several occasions. Khallad was another veteran mujahid, like much of his family. His father had been expelled from Yemen because of his extremist views. Khallad had grown up in Saudi Arabia, where his father knew Bin Laden, Abdullah Azzam, and Omar Abdel Rahman (the "Blind Sheikh").

Question: "Was the white house on the initial list of targets developed by KSM, Atef, and Bin Laden?"

Answer: "Yes"

Response: yes

As food is pushed along, it undergoes digestion. Digestion is the process of breaking down food into nutrients. There are two types of digestion: mechanical digestion and chemical digestion. Mechanical digestion occurs when large chunks are turned into smaller chucks. Perhaps not surprisingly, this happens when you chew your food. Once you swallow the food, your stomach also does some of this work. Chemical digestion occurs when food is broken down into useful nutrients. This is a chemical process that begins as you start to chew your food. The saliva in your mouth starts this process. Once you swallow, the acid in your stomach further breaks down food. From the stomach, the foods moves into the small intestine. In the small intestines, another set of chemicals goes to work. Are you surprised? Your small intestine, and not your stomach, does most of the work!

Question: "What does mechanical digestion involve?"

Answer: "Spitting out your food"

Response: no

For much of the world, the Algarve is synonymous with Portugal, yet the Portuguese will tell you the exact opposite: the region has little in common with the rest of the country. The southern stretch of coast is more reminiscent of a North African landscape than a European one. It has no cosmopolitan cities, like Lisbon and Porto, which are farther north. Most of Portugal is known for quaint towns, medieval castles, and grand palaces. The Algarve is more recognizable for impenetrable blocks of tourist apartments, hotels, and meticulously manicured golf courses. And beaches. Think Algarve and the mind pictures long, glorious stretches of golden sands, secluded coves framed by odd ochre-colored rock formations, and deep green waters. With about 160 km (100 miles) of coastline, Portugal's southern province is one of Europe's premier beach destinations. The occasionally chilly ocean is the Atlantic, but the Algarve has a sultry Mediterranean feel. Its consistent climate is the best in Portugal, and one of the kindest in the world: more than 250 days of sunshine a yearmore than almost any other international resort area. The moderating effect of the Gulf Stream produces a fresh springtime breeze throughout winter, and in late January and February, white almond blossoms blanket the fields. In summer the heat is intense but rarely unbearable, and regardless, beautiful beaches and innumerable pools are always just a dive away. Magnificent year-round weather has made the Algarve a huge destination for sporting vacations. Superb golf facilities aboundseveral with tees dramatically clinging to cliffs and fairways just skirting the edge of the oceanand horseback riding, tennis, big-game fishing, sailing, and windsurfing are immensely popular. Sports, beaches and hospitable weathernot to mention easily organized package vacationsare surely the reasons the Algarve receives as many visitors as the rest of Portugal in its entirety. But it's not just international tourists that descend on the Algarve; many Portuguese from Lisbon and elsewhere in the north have holiday homes and spend their summer vacations here. The coast is neatly divided into the rugged Barlavento to the west and the flat beauty of Sotavento to the east. West is where you'll find the famous orange cliffs and surreal eroded rock stacks.

Question: "What southern stretch of coast is more reminiscent of a North African landscape than a European one?"

Answer: "South Africa"

Response:
no