Problem: I read this background article the other day: One result of air pollution is acid rain. Acid rain is precipitation with a low (acidic) pH. This rain can be very destructive to wildlife. When acid rain falls in forests, freshwater habitats, or soils, it can kill insects and aquatic life. It causes this damage because of its very low pH. Sulfur oxides and nitrogen oxides in the air both cause acid rain to form ( Figure below ). Sulfur oxides are chemicals that are released from coal-fired power plants. Nitrogen oxides are released from motor vehicle exhaust. I am facing a new situation today: Beijing recently significantly increased the amount of cars on the roads there through mandatory price cuts for all motor vehicles. In Montreal, the number of cars on the roads has decreased drastically recently through public transportation initiatives and public advertising campaigns encouraging biking and walking. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which area will produce rain with lower pH?

A: Beijing

Problem: I read this background article the other day: Extending the period of time over which a force acts in order to lessen the force is a common practice in design. Padding in shoes and seats allows the time to increase. The front of automobiles are designed to crumple in an accident; this increases the time the car takes to stop. Similarly, barrels of water or sand in front of abutments on the highway and airbags serve to slow down the stoppage time. These changes all serve to decrease the amount of force it takes to stop the momentum in a car crash, which consequently saves lives. I am facing a new situation today: Keith designs car seats. He noticed that some other car seats didn't have any padding. He marked it as case A. On the other hand, most of the seats he designed had padding. He marked it as case B. Keith needed to know pros and cons of both designs. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which case would more likely make products unsafe, case A or case B?

A: case A

Problem: I read this background article the other day: The strength of an acid refers to its ability or tendency to lose a proton. A strong acid is one that completely dissociates in water; in other words, one mole of a strong acid HA dissolves in water yielding one mole of H+ and one mole of the conjugate base, A, and none of the protonated acid HA. In contrast, a weak acid only partially dissociates and at equilibrium both the acid and the conjugate base are in solution. Examples of strong acids are hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid (HBr), perchloric acid (HClO4), nitric acid (HNO3) and sulfuric acid (H2SO4). In water each of these essentially ionizes 100%. The stronger an acid is, the more easily it loses a proton, H+. Two key factors that contribute to the ease of deprotonation are the polarity of the HA bond and the size of atom A, which determines the strength of the HA bond. Acid strengths are also often discussed in terms of the stability of the conjugate base. I am facing a new situation today: David is a chemical engineer. Yesterday, he was working on two samples, sample A and sample B. Sample A was a strong acid, and sample B was a weak acid. David needed to find the differences between them. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would sample B dissociate in water less or more than sample A?

A: less

Problem: I read this background article the other day: Distance decay is a geographical term which describes the effect of distance on cultural or spatial interactions. The distance decay effect states that the interaction between two locales declines as the distance between them increases. Once the distance is outside of the two locales' activity space, their interactions begin to decrease. With the advent of faster travel, distance has less effect than it did in the past, except where places previously connected by now-abandoned railways, for example, have fallen off the beaten path. Advances in communications technology, such as telegraphs, telephones, broadcasting, and internet, have further decreased the effects of distance.[1] I am facing a new situation today: Chad invested massively in railways and highways over the past decade. They also funded many IT projects and telecom infrastructure. On the other hand, Bahrain invested less, and didn't do much to improve communication pathways and technologies between different villages. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which country experiences less interaction between two locales?

A:
Bahrain