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: "Approximately what year was the Las Vegas Valley covered by a prehistoric lake?"

OPTIONS:
- no
- yes

Answer: "Around 3000 b.c"

Response: no

Mechanical energy is a combination of the energy of motion or position. This type of energy describes objects that are moving or could move. A moving ball can have energy from motion. An arrow can also have the energy of motion. Both are types of mechanical energy. Can you think of some other examples? Where does the energy of motion come from? It comes from the energy created by position. This energy is stored energy. This means it is not moving yet, but it has the potential to move. How can you store energy? The arrow gains energy from the drawn bow. As the arrow is released, the bow releases its stored energy and puts the arrow into motion. Can you think of some other ways to store energy using position?

Question: "What type of energy do a moving arrow or ball have?"

Response: "Mechanical energy"
OPTIONS:
- no
- yes

A: yes

Problem: Before the establishment of the People's Republic, Albania's illiteracy rate was as high as 85%. Schools were scarce between World War I and World War II. When the People's Republic was established in 1945, the Party gave high priority to wiping out illiteracy. As part of a vast social campaign, anyone between the ages of 12 and 40 who could not read or write was mandated to attend classes to learn. By 1955, illiteracy was virtually eliminated among Albania's adult population. Today the overall literacy rate in Albania is 98.7%; the male literacy rate is 99.2% and female literacy rate is 98.3%. With large population movements in the 1990s to urban areas, the provision of education has undergone transformation as well. The University of Tirana is the oldest university in Albania, having been founded in October 1957.

Question: "What year was Albania's illiteracy rate 85%?"

Answer: "1990"

OPTIONS:
- no
- yes
Answer: no

Question:
The Glory of Melaka: In the early days, if you were not a pirate or a mosquito, Melaka was not much of a place to live. The land was infertile, just a swampy plain, the river small and sluggish. But it had a sheltered harbor, protected from the monsoons by neighboring Sumatra. Later, the strategic location and deep-water channel close to the coast brought in the bigger vessels of the trade-wind traffic crossing the Indian Ocean. The first to realize the larger commercial potential, as so often throughout the country's subsequent history, were the Chinese. In 1409, under a new directive from Emperor Chu Ti to pursue trade in the South Seas and the Indian Ocean, a Chinese fleet of 50 ships headed by Admiral Cheng Ho called in at Melaka. They made Parameswara an offer he could not refuse: port facilities and an annual financial tribute in exchange for Chinese protection against the marauding Thais. In 1411, Parameswara took the money to Beijing himself, and the emperor gratefully made him a vassal king. Twenty years later, the Chinese withdrew again from the South Seas trade. The new ruler of Melaka, Sri Maharajah, switched his allegiance to the Muslim trading fraternity by marrying into the Muslim faith, wedding the daughter of a sultan in Sumatra. Islam won its place in Malaya not by conquestas had been the case in North Africa and Europebut by trade, dynastic alliances, and peaceful preaching. Bengali peddlers had already brought the faith to the east coast. In Melaka and throughout the peninsula, Islam thrived as a strong, male-dominated religion of individuality, offering dynamic leadership and preaching brotherhood and self-relianceall qualities ideally suited to the coastal trade. At the same time, Sufi mystics synthesized Islamic teaching with local Malay traditions of animistic magic and charisma, though Islam did not become the state religion until Muzaffar Shah became sultan of Melaka (14461459). But the key figure in the sultanate was Tun Perak, bendahara (prime minister) and military commander. He expanded Melaka's power along the west coast and down to Singapore and the neighboring Bintan islands. He also had orang laut pirates patrolling the seas to extort tribute from passing ships. After Ailied district chiefs had repelled assaults from Thai-controlled armies from Pahang, Tun Perak personally led a famous victory over a Thai fleet off Batu Pahat in 1456. After reading the above, is "Tun Perak" the correct answer to the question "Who was the first emperor to notice the commercial potential to Melaka?"? OPTIONS:
- no
- yes

Answer:
no

You may wonder if there are other examples of static discharge. The answer is yes. Lightning is a form of static discharge. It is much more dramatic than what happens between you and the door knocker, but it is the same principle. You can see how it occurs in the following diagram and animation. You have no doubt seen lightning in a rainstorm. What does lighting have to do with static electricity? As it turns out, everything! During a rainstorm, clouds develop regions of different charges. This happens due to the movement of air molecules, water drops, and ice particles. The negative charges are concentrated at the base of the clouds. The positive charges are concentrated at the top. The negative charges repel electrons on the ground below. The ground then becomes positively charged. Over time the differences increase. Eventually the electrons are discharged. This is what we see as lightning. You can watch an awesome slow-motion lightning strike below.

Question: "What do we see when electrons are discharged?"

OPTIONS:
- no
- yes

Answer: "Rain"

Response:
no