Given the background: Some materials have negative heats of solution; the dissolution of one of these solutes in water is an exothermic process. Heat is released, causing a net increase in the temperature of the solution. Conversely, other substances have positive heats of solution. For example, the dissolution of potassium nitrate in water is an endothermic process. The resulting absorption of energy causes the solution to become colder. Calculations involving heats of solutions follow the same basic approach that we have used with other enthalpy problems. and the situation: A scientist is in the lab testing mixing water with different chemicals. While working with chemical A he notes that the water becomes colder after combining them. With chemical B the water becomes much warmer. Answer the following question: Given he adds a new chemical, chemical C and notes that it is an exothermic process, will the temperature have increased or decreased?
Ans: decreased

Given the background: A red giant star is a star with a mass like the Sun that is in the last phase of its life, when Hydrogen fusion reactions in the core decrease due to the lack of fuel. With the gravitational collapse of the core, the fusion reactions now occur in a shell surrounding the core. The outer layer of the star expands enormously up to 1000 times the size of the Sun. When the Sun becomes a red giant, its volume will include the orbit of Mercury and Venus and maybe even Earth. The increased size increases the luminosity even though the outer layer cools to only 3000 K or so. The cooler outer layer causes it to be a red star. After a few more million years, the star evolves into a white dwarf-planetary nebula system. and the situation: Two stars have just been discovered that are identical in terms of chemical composition. The scientist who discovered them was given the right to name them, and he chose the names Enterprise and Vader. As said before, these stars are very similar, but the main difference is that Vader is a red giant, and Enterprise is not. Scientists are very eager to study these two newly discovered stars and see if they can learn anything new from them. Answer the following question: Does Enterprise have more or less fuel than Vader?
Ans: more

Given the background: Fish mortality is a parameter used in fisheries population dynamics to account for the loss of fish in a fish stock through death. The mortality can be divided into two types: Natural mortality: the removal of fish from the stock due to causes not associated with fishing. Such causes can include disease, competition, cannibalism, old age, predation, pollution or any other natural factor that causes the death of fish. In fisheries models natural mortality is denoted by (M).[1] Fishing mortality: the removal of fish from the stock due to fishing activities using any fishing gear.[1] It is denoted by (F) in fisheries models. and the situation: Two lakes had been stocked with fish two years before.Blue lake had an abundant fish stock because nobody fished there, but Green lake was open for fishing. Blue lake had some pollution, cannibalism and disease problems. Answer the following question: Which lake had more cannibalism problems?
Ans: Blue lake

Given the background: Rain dissolves fertilizer in the soil. Runoff carries it away. The fertilizer ends up in bodies of water, from ponds to oceans. The nitrogen is a fertilizer in the water bodies. Since there is a lot of nitrogen it causes algae to grow out of control. Figure below shows a pond covered with algae. Algae may use up so much oxygen in the water that nothing else can grow. Soon, even the algae die out. Decomposers break down the dead tissue and use up all the oxygen in the water. This creates a dead zone. A dead zone is an area in a body of water where nothing grows because there is too little oxygen. There is a large dead zone in the Gulf of Mexico. You can see it Figure below . and the situation: Leaf farm and Plum farm provided the neighboring counties with quality produce year-round. plum farm used conventional farming methods such as fertilizer and pesticides, while Leaf farm used alternative eco-friendly methods only. Answer the following question: Which farm caused more fertilizer to reach the oceans?
Ans: Plum