Question: Los Angeles receives a steady year-long supply of high amounts of sunlight and wind. Because of this, Los Angeles is able to power many of its buildings and factories using renewable resources. Las Vegas, however, receives barely any sunlight or wind throughout the entire year. As a result, they use little renewable resources and instead power most of the city through non-renewable resources like fossil fuels. Which city, Los Angeles or Las Vegas, emits less pollutants? Hint: Natural resources include energy, minerals and other materials. Natural resources may be renewable or non-renewable. Non-renewable resources cannot be replaced. When they're gone, they're gone. Renewable resources can be replaced. They can supply human activities forever. Fossil fuels are crucial for modern human society. Fossil fuels are essential for transportation, industry and agriculture. Renewable energy resources tend to be clean. They emit fewer pollutants and greenhouse gases than fossil fuels. Renewable resources often have other problems. They are more costly and less efficient than fossil fuels. Still, they have many advantages. Research is going into developing renewable resources. Conservation is the best way to increase resource availability. Anyone can conserve! You and your family can. Society can. The world can. Just reduce, reuse, recycle.
Answer: Los Angeles

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. Would matter B have higher or lower density than matter C? 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.
Answer: higher

Question: David was visiting the natural history museum. He noticed two charts that showed the climatic conditions of the earth in two time periods, time A and time B. Time A showed earth's overall climate in the sixteenth century when there were less greenhouse gases in the atmosphere. And time B showed earth's overall climate in the present century with more greenhouse gases in the atmosphere. David found some interesting differences between these two charts. Would time A see less or more trapped terrestrial radiation than time B? Hint: Greenhouse Effect: The solar energy reaching the surface of the Earth is concentrated in short wavelengths, which can easily penetrate the greenhouse gases, such as carbon dioxide and methane. The Earth, however, is cooler than the sun and it radiates its heat in the form of energy in the far infrared range. These longer wavelengths are partially absorbed by the greenhouse gases and some of the solar heat is returned to Earth. At a certain temperature these processes are in equilibrium and the surface temperature of the Earth is stable. However, if more greenhouse gases are put in the atmosphere the amount of trapped terrestrial radiation increases, leading to an increase in global temperature.
Answer:
less