I have a new situation: Two twin sisters, Bianca and Rosa, were exposed to high levels of air pollution. While Bianca was exposed mostly to indoor pollution, Rosa was heavily exposed to outdoor pollution. But I can use this background: Recall that air pollution is due to chemical substances and particles released into the air mainly by human actions. When most people think of air pollution, they think of the pollution outdoors. But it is just as easy to have indoor air pollution. Your home or school classroom probably doesn't get much fresh air. Sealing up your home reduces heating and cooling costs. But this also causes air pollution to stay trapped indoors. And people today usually spend a majority of their time indoors. So exposure to indoor air pollution can become a significant health risk. What is an answer for this question: Which sister got less fresh air?
Ans: Bianca

I have a new situation: There are two planets, Glarnak and Bornak, that share the same atmospheric composition. The planets have nearly identical ecosystems and topography. The main difference between the two planets is the level of global warming on each planet. Glarnak is experiencing a strong impact from global warming. Bornak, though, is experiencing practically no effects of global warming. But I can use this background: Pollutants also affect the atmosphere through their contribution to global warming. Global warming is an increase in the Earth's temperature. It is thought to be caused mostly by the increase of greenhouse gases like carbon dioxide. Greenhouse gases can be released by factories that burn fossil fuels. Over the past 20 years, burning fossil fuels has produced about three-quarters of the carbon dioxide from human activity. The rest of the carbon dioxide in the atmosphere is there because of deforestation, or cutting down trees ( Figure below ). Trees absorb carbon dioxide during cellular respiration, so when trees are cut down, they cannot remove carbon dioxide from the air. What is an answer for this question: Which planet probably produces less carbon dioxide?
Ans: Bornak

I have a new situation: As a science experiment for his school homework, Kendra is putting two ice cubes on separate pans and then putting those pans on burners set to different temperatures. Ice cube A is set on top of a burner set to a low temperature, and ice cube B is placed on a burner set quite a bite higher. One minute later, Kendra begins writing down what she sees happening to the ice cubes. But I can use this background: For most substances, when the temperature of the solid is raised high enough, the substance changes to a liquid, and when the temperature of the liquid is raised high enough, the substance changes to a gas. We typically visualize a solid as tiny particles in constant motion held together by attractive forces. As we add heat to the solid, the motion, or the kinetic energy, of the particles increases. At some temperature, the motion of the particles becomes great enough to overcome the attractive forces. The thermal energy that was added to the solid up to this point was absorbed by the solid as kinetic energy, increasing the speed of the molecules. The lowest temperature at which the particles are able to exist in the liquid form is called the melting point . What is an answer for this question: Has ice cube B absorbed more or less thermal energy than ice cube A?
Ans: more

I have a new situation: Calving is sitting in his kitchen when he decides to play around with some ice and water. He takes an ice cube out of the freezer and puts it on a plate on his kitchen table. He then takes a glass of water and puts it into the freezer. He is curious to see if the ice cube will melt before the water freezes. But I can use this background: In the study of thermochemical processes, things are viewed from the point of view of the system. A chemical reaction or physical change is endothermic if heat is absorbed by the system from the surroundings. In the course of an endothermic process, the system gains heat from the surroundings and so the temperature of the surroundings decreases. The quantity of heat for a process is represented by the letter . The sign of for an endothermic process is positive because the system is gaining heat. A chemical reaction or physical change is exothermic if heat is released by the system into the surroundings. Because the surroundings is gaining heat from the system, the temperature of the surroundings increases. The sign of for an exothermic process is negative because the system is losing heat. What is an answer for this question: Is the sign for the reaction of the water freezing positive or negative?
Ans: negative