Problem: 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: Near the city of Middleton, there are two forests. The Trine forest is a forest tightly packed with trees. Trine has hardly any large open spaces on the ground. The Jimpy forest, on the other hand, is much more open. It has some large areas in the forest that are perfect for camping or for children to play in due to the lack of trees. Answer the following question: Which forest would require a higher temperature to burn?

A: Trine

Problem: Given the background: Excess intake of calcium may cause hypercalcaemia. However, because calcium is absorbed rather inefficiently by the intestines, high serum calcium is more likely caused by excessive secretion of parathyroid hormone (PTH) or possibly by excessive intake of vitamin D, both which facilitate calcium absorption. It may also be due to bone destruction that occurs when tumours metastasize within bone. All these conditions result in excess calcium salts being deposited in the heart, blood vessels, or kidneys. Symptoms include anorexia, nausea, vomiting, memory loss, confusion, muscle weakness, increased urination, dehydration, and metabolic bone disease. Chronic hypercalcaemia typically leads to calcification of soft tissue and its serious consequences: for example, calcification can cause loss of elasticity of vascular walls and disruption of laminar blood flowand thence to plaque rupture and thrombosis. Conversely, inadequate calcium or vitamin D intakes may result in hypocalcaemia, often caused also by inadequate secretion of parathyroid hormone or defective PTH receptors in cells. Symptoms include neuromuscular excitability, which potentially causes tetany and disruption of conductivity in cardiac tissue. and the situation: Two brothers went to the doctor's office for a medical exam and blood tests. Dan found out he is healthy and had normal blood cholesterol and calcium levels. Ben however, was told that he had a disease called hypercalcaemia and had to start a treatment for that. Answer the following question: Which brother experienced less nausea?

A: Dan

Problem: Given the background: Chemical equilibrium was studied by French chemist Henri Le Chatelier (1850-1936), and his description of how a system at equilibrium responds to a change in conditions has become known as Le Chatelier's principle . This principle states that when a chemical system is at equilibrium and is disturbed by a stress, the system will respond by attempting to counteract that stress until a new equilibrium is established. Stresses to a chemical system include changes in the concentrations of reactants or products, changes in the temperature of the system, or changes in the pressure of the system. We will discuss each of these stresses separately. In each case, the change to the equilibrium position will cause either the forward or reverse reaction to be favored over the opposite process. When the forward reaction is favored, the concentrations of the products increase, and the concentrations of the reactants decrease. When the reverse reaction is favored, the concentrations of the products decrease, and the concentrations of the reactants increase. and the situation: David was conducting experiments on chemical equilibrium in the chemistry lab. First, he took a chemical system that was at equilibrium. He labeled it as case E. Then he changed the temperature of the system. He labeled that experiment as case T. Finally, he observed two more experiments, case A and case B. In case A forward reaction was favored, and in case B reverse reaction was favored. Answer the following question: In which case the reactants concentration would decrease, case A or case B?

A: case A

Problem: Given the background: Nearsightedness, or myopia, is the condition in which nearby objects are seen clearly, but distant objects appear blurry. The Figure below shows how it occurs. The eyeball is longer (from front to back) than normal. This causes images to be focused in front of the retina instead of on the retina. Myopia can be corrected with concave lenses. The lenses focus images farther back in the eye, so they fall on the retina instead of in front of it. and the situation: Two siblings went to the eye doctor, they needed eyeglasses. As it turned out, Ann had myopia, and Jane had farsightedness. They both bought eyeglasses. Answer the following question: Which sister had normal eyeballs?

A:
Jane