I can use this background: Human beings invented agriculture about 10,000 years ago. This provided a bigger, more dependable food supply. It also allowed people to settle down in villages and cities for the first time. Birth rates went up because there was more food and settled life had other advantages. Death rates also rose because of crowded living conditions and diseases that spread from domestic animals. Because the higher birth rates were matched by higher death rates, the human population continued to grow very slowly. Now, I have a new situation: Harry and Kim studied ancient humans. Kim studied a 15000 year-old settlement, before humans invented agriculture, while Harry studied a 5000 year-old village. Answer this question please: Which student studied about a village that had fewer diseases that spread from domestic animals?
Ans: Kim

I can use this background: Many different chemical substances cause cancer. Dozens of chemicals in tobacco smoke, including nicotine, have been shown to cause cancer ( Figure below ). In fact, tobacco smoke is one of the main sources of chemical carcinogens. Smoking tobacco increases the risk of cancer of the lung, mouth, throat, and bladder. Using smokeless tobacco can also cause cancer. Other chemicals that cause cancer include asbestos, formaldehyde, benzene, cadmium, and nickel. Now, I have a new situation: Two ladies sit in a coffee shop. Patty smokes three packs of cigarettes a day, but her good friend Julie, doesn't smoke. They are both 65 years old. They are enjoying a coffee. Answer this question please: Which lady is less exposed to cancer?
Ans: Julie

I can use this background: Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. Nitrogen is a fertilizer in the water. Since there is a lot of nitrogen, it causes algae to grow out of control. Pictured below is a pond covered with algae ( Figure below ). Algae use up carbon dioxide in the water. After the algae die, decomposers break down the dead tissue. The decomposers use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico ( Figure below ). The U.S. states outlined on the map have rivers that drain into the Gulf of Mexico. The rivers drain vast agricultural lands. The water carries fertilizer from these areas into the Gulf. Now, I have a new situation: Iceland and Ireland both used agriculture as a the main component of their economies. Ireland used lots of fertilizer and had big environmental problems as a result. Iceland does a lot of greenhouse agriculture using geothermal energy, so it is more protective towards the environment. Answer this question please: Which country caused fewer decomposers to break down dead algae?
Ans: Iceland

I can use this background: In common everyday speech, speed of sound refers to the speed of sound waves in air. However, the speed of sound varies from substance to substance: sound travels most slowly in gases; it travels faster in liquids; and faster still in solids. For example, (as noted above), sound travels at 343 m/s in air; it travels at 1,480 m/s in water (4.3 times as fast as in air); and at 5,120 m/s in iron (about 15 times as fast as in air). In an exceptionally stiff material such as diamond, sound travels at 12,000 metres per second (27,000 mph);[1] (about 35 times as fast as in air) which is around the maximum speed that sound will travel under normal conditions. Now, I have a new situation: John and Keith are neighbors. They have been pondering about how to communicate with each other in a doomsday scenario when all the electronic devices would be useless. They connected their houses with three ducts. One of the ducts is filled with air; they called it channel A. Another duct is filled with water; they called it channel B. And the last duct is filled with iron; they called it channel C. They can now transmit sound with these channels of communication; in case, disaster strikes. Answer this question please: Which channel would be the slowest, channel A, channel B, or channel C?
Ans: channel A