Problem: I read this background article the other day: It would be very unadvisable to place a can of soup over a campfire without venting the can. As the can heats up, it may explode. The kinetic-molecular theory explains why. The air inside the rigid can of soup is given more kinetic energy by the heat coming from the campfire. The kinetic energy causes the air molecules to move faster and they impact the container walls more frequently and with more force. The increase in pressure inside may eventually exceed the strength of the can and it will explode. An additional factor is that the soup may begin boiling which will then aid even more gas and more pressure to the inside of the can. I am facing a new situation today: Adam is out camping and is ready to eat. He gets a can of baked beans and puts it over his campfire. He however did not puncture the can before doing so. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Will the chance that the can of beans explodes increase or decrease not being vented over the fire?

A: increase

Problem: I read this background article the other day: In the natural world, ants of some species (initially) wander randomly, and upon finding food return to their colony while laying down pheromone trails. If other ants find such a path, they are likely not to keep travelling at random, but instead to follow the trail, returning and reinforcing it if they eventually find food (see Ant communication). Over time, however, the pheromone trail starts to evaporate, thus reducing its attractive strength. The more time it takes for an ant to travel down the path and back again, the more time the pheromones have to evaporate. A short path, by comparison, gets marched over more frequently, and thus the pheromone density becomes higher on shorter paths than longer ones. Pheromone evaporation also has the advantage of avoiding the convergence to a locally optimal solution. If there were no evaporation at all, the paths chosen by the first ants would tend to be excessively attractive to the following ones. In that case, the exploration of the solution space would be constrained. The influence of pheromone evaporation in real ant systems is unclear, but it is very important in artificial systems.[8] I am facing a new situation today: Ricky, an entomologist, is observing an ant colony in his back yard. After some observation, he discovers that all the ants travel down one of two distinct paths in order to find food to bring back to the colony. After taking some measurements, Ricky sees that path A is approximately 100 meters in length, and path B is approximately 150 meters in length. Ricky is now trying to make some scientific conclusions based on these observations. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which path will have higher pheromone density?

A: path A

Problem: I read this background article the other day: An allergy is a disease in which the immune system makes an inflammatory response to a harmless antigen . Any antigen that causes an allergy is called an allergen. Allergens may be inhaled or ingested, or they may come into contact with the skin. Two common causes of allergies are shown in Figure below . Inhaling ragweed pollen may cause coughing and sneezing. Skin contact with oils in poison ivy may cause an itchy rash. Other common causes of allergies include dust mites, mold, animal dander, insect stings, latex, and certain food and medications. Symptoms of a common allergy such as pollen can include sneezing, a runny nose, nasal congestion and itchy, watery eyes. I am facing a new situation today: Two groups f people presented allergy symptoms. Group Alpha inhaled some allergens, but they were in a very protected environment, while Group Beta ingested some allergens and was exposed to a wide variety of other allergens. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which group had some people that were exposed to latex?

A: Group Beta

Problem: I read this background article the other day: Catalytic converters in cars increase the rates of several important reactions. Unburned hydrocarbons can more easily be converted to carbon dioxide and water in the presence of a catalyst. Additionally, carbon monoxide (a harmful gas produced by incomplete combustion of fuel) is further oxidized to carbon dioxide, and nitrous oxide compounds (which contribute to smog and acid rain) are transformed back into nitrogen and oxygen gases. By passing car exhaust over these catalysts before their release into the air, the emissions from a combustion engine are made into much less harmful substances, resulting in a much cleaner atmosphere. I am facing a new situation today: John is an automotive enthusiast. He was visiting the auto show in his city. Two cars caught his attention, car A and car B. Car A was newer and it had catalytic converter. On the contrary, car B was older and didn't have catalytic converter. But he found the design of older car more attractive. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which car would emit less carbon monoxide, car A or car B?

A:
car A