Problem: John wanted to see how he would fare in high altitude compared to ground-level. So, he first measured his responses in ground-level. He labeled this part of the study as case A. Then he board on an airplane to reach high altitude, and measured his responses there. He labeled this part of the study as case B. Now, John knows how he needs to prepare for a high altitude hiking. Which case would see higher atmospheric pressure, case A or case B? Hint: As shown here, pressure decreases to less than 25% of ground-level atmospheric pressure when we get to an altitude of about six miles. Since this is a common cruising altitude for commercial airplanes, pressurized cabins are needed for the comfort and survival of the passengers. This is because the density of the air decreases along with the decreasing air pressure, so there is less oxygen in a breath of air. You've probably noticed this effect in high-mountain areas, as it often feels harder to breath.

A: case A

Problem: Given the question: Bill was studying the states of matter. First, he selected a matter with low boiling point. He labeled it as matter A. To compare it with a well-known matter he selected water. He labeled it as matter B. He also selected ice, which he labeled as matter C. He is now better prepared to compare their states. Which matter would be in gaseous state at room temperature, matter A or matter B? Hint: Hydrogen bonds cause water to have a relatively high boiling point of 100C (212F). Because of its high boiling point, most water on Earth is in a liquid state rather than in a gaseous state. Water in its liquid state is needed by all living things. Hydrogen bonds also cause water to expand when it freezes. This, in turn, causes ice to have a lower density (mass/volume) than liquid water. The lower density of ice means that it floats on water. For example, in cold climates, ice floats on top of the water in lakes. This allows lake animals such as fish to survive the winter by staying in the water under the ice.
++++++++++++++++++++++++++++++++
The answer is:
matter A

input question: Brett and Scott were both studying bacteria for their exam. Scott read more about nitrogen-fixating and sulfate-reducing bacteria, while his colleague Brett read more about non-respiratory anaerobe bacteria and facultative anaerobes. Which student read less about sulfate reduction? Hint: In many ways, bacterial metabolism provides traits that are useful for ecological stability and for human society. One example is that some bacteria have the ability to fix nitrogen gas using the enzyme nitrogenase. This environmentally important trait can be found in bacteria of most metabolic types listed above. This leads to the ecologically important processes of denitrification, sulfate reduction, and acetogenesis, respectively. Bacterial metabolic processes are also important in biological responses to pollution; for example, sulfate-reducing bacteria are largely responsible for the production of the highly toxic forms of mercury (methyl- and dimethylmercury) in the environment. Non-respiratory anaerobes use fermentation to generate energy and reducing power, secreting metabolic by-products (such as ethanol in brewing) as waste. Facultative anaerobes can switch between fermentation and different terminal electron acceptors depending on the environmental conditions in which they find themselves.???
output answer: Brett

John liked studying about the planets in our solar system. He recently studied and made comparisons between Earth's and Venus's atmosphere. He was amazed with what he found out. Which planet has no clouds made of sulfur dioxide? Hint: Clouds on Earth are made of water vapor. Venus's clouds are a lot less pleasant. They are made of carbon dioxide, sulfur dioxide and large amounts of corrosive sulfuric acid! The atmosphere of Venus is so thick that the pressure on the surface of Venus is very high. In fact, it is 90 times greater than the pressure at Earth's surface! The thick atmosphere causes a strong greenhouse effect. As a result, Venus is the hottest planet. Even though it is farther from the Sun, Venus is much hotter even than Mercury. Temperatures at the surface reach 465C (860F). That's hot enough to melt lead!
----
Answer: Earth

Q: The ozone layer helps organisms by protecting them from Sun's ultraviolet radiation. To find the usefulness of ozone layer Mike wanted to see how much ozone are there in the atmosphere. He then collected three samples of atmosphere, sample A sample B, and sample C. Sample A was collected from the upper portion of the stratosphere. Sample B was collected from the lower portion of the stratosphere. Sample C was collected from the lower atmosphere. Which sample would have higher concentration of ozone, sample B or sample C? Hint: The ozone layer is contained within the stratosphere. In this layer ozone concentrations are about 2 to 8 parts per million, which is much higher than in the lower atmosphere but still very small compared to the main components of the atmosphere. It is mainly located in the lower portion of the stratosphere from about 1535 km (9.321.7 mi; 49,000115,000 ft), though the thickness varies seasonally and geographically. About 90% of the ozone in Earth's atmosphere is contained in the stratosphere.
A: sample B

[Q]: Matt is preparing food for a dinner party in his kitchen. His guests will be arriving shortly, so he fills up a pitcher with some water and puts it in the freezer to cool it down. He then takes a solid block of ice out of his freezer that he is planning to carve into a sculpture of some kind. Before he can start sculpting, there is a knock on his door that he must answer. Would the water or the ice require more energy to transform into a gas? Hint: As Figure above shows, the distance between particles is much smaller for the solid and liquid states than for the gas state. In the solid state, particles are fixed in place, while particles are more free to move in the liquid and gas states. The particles in the solid and liquid states "stick together," but in the gas state, they move freely about the container. In general, it requires energy to separate individual particles. If we want to make a solid adopt a liquid form, we can add energy in the form of heat, increasing the temperature of the substance. Conversely, if we want to convert a substance from a gas to a liquid or from a liquid to a solid, we remove energy from the system and decrease the temperature. Pressure also plays an important role in changes of state, which will be discussed later on. We will study these difference in greater detail in the chapter States of Matter.
****
[A]:
ice