Given the background: When humans dig up and use fossil fuels, we have an impact on the carbon cycle ( Figure below ). This carbon is not recycled until it is used by humans. The burning of fossil fuels releases more carbon dioxide into the atmosphere than is used by photosynthesis. So, there is more carbon dioxide entering the atmosphere than is coming out of it. Carbon dioxide is known as a greenhouse gas , since it lets in light energy but does not let heat escape, much like the panes of a greenhouse. The increase of greenhouse gasses in the atmosphere is contributing to a global rise in Earth's temperature, known as global warming or global climate change. and the situation: Greg is an environmental scientist. He wants to know how earth's atmosphere differed in two different time. To that end, he selected two time periods, time A and time B. Time A is set in the year one thousand when using fossil fuels was not very common. Time B is set in the year two thousand when fossil fuels are used in large quantities. Answer the following question: Would time B have lower or higher earth temperature than time A?
Ans: higher

Given the background: Allergy symptoms can range from mild to severe. Mild symptoms might include itchy eyes, sneezing, and a runny nose. Severe symptoms can cause difficulty breathing, which may be life threatening. Keep in mind that it is the immune system and not the allergen that causes the allergy symptoms. Allergy symptoms can be treated with medications such as antihistamines. Severe allergic reactions may require an injection of the hormone epinephrine. These treatments lessen or counter the immune system's response. and the situation: Two sisters both had allergies. Ann had mild allergies, while Jo had to be very careful because she experienced severe allergic reactions before. Answer the following question: Which sister might have had sneezing?
Ans: Ann

Given the background: The brains of all mammals have a unique layer of nerve cells covering the cerebrum. This layer is called the neocortex (the pink region of the brains in Figure above ). The neocortex plays an important role in many complex brain functions. In some mammals, such as rats, the neocortex is relatively smooth. In other mammals, especially humans, the neocortex has many folds. The folds increase the surface area of the neocortex. The larger this area is, the greater the mental abilities of an animal. and the situation: Two students read about brains in the animal kingdom. Tom read more about the brains of mammals, while Reed learned more about the brains of amphibians. Answer the following question: Which student learned less about the human neocortex?
Ans: Reed

Given the background: Wildfires occur when all the necessary elements of a fire triangle come together in a susceptible area: an ignition source is brought into contact with a combustible material such as vegetation, that is subjected to enough heat and has an adequate supply of oxygen from the ambient air. A high moisture content usually prevents ignition and slows propagation, because higher temperatures are needed to evaporate any water in the material and heat the material to its fire point. Dense forests usually provide more shade, resulting in lower ambient temperatures and greater humidity, and are therefore less susceptible to wildfires. Less dense material such as grasses and leaves are easier to ignite because they contain less water than denser material such as branches and trunks. Plants continuously lose water by evapotranspiration, but water loss is usually balanced by water absorbed from the soil, humidity, or rain. When this balance is not maintained, plants dry out and are therefore more flammable, often a consequence of droughts.A wildfire front is the portion sustaining continuous flaming combustion, where unburned material meets active flames, or the smoldering transition between unburned and burned material. As the front approaches, the fire heats both the surrounding air and woody material through convection and thermal radiation. First, wood is dried as water is vaporized at a temperature of 100 C (212 F). Next, the pyrolysis of wood at 230 C (450 F) releases flammable gases. Finally, wood can smoulder at 380 C (720 F) or, when heated sufficiently, ignite at 590 C (1,000 F). Even before the flames of a wildfire arrive at a particular location, heat transfer from the wildfire front warms the air to 800 C (1,470 F), which pre-heats and dries flammable materials, causing materials to ignite faster and allowing the fire to spread faster. High-temperature and long-duration surface wildfires may encourage flashover or torching: the drying of tree canopies and their subsequent ignition from... and the situation: David is an environmental scientist. He needed to find causes of wildfires and suggest preventive measures. First, he visited a dense forest. He marked it as location A. Then he visited a grassland, which he marked as location B. After that, he visited a location where he did not find any sign of drought. He marked it as time A. He then visited the same location a year later, and found that the place was facing a severe drought. He marked it as time B. Answer the following question: Which place would have higher ambient temperature, locaion A or location B?
Ans: location B