Answer the following question given this paragraph: In Silver Springs, the TLTE between the first two trophic levels was approximately 14.8 percent. The low efficiency of energy transfer between trophic levels is usually the major factor that limits the length of food chains observed in a food web. The fact is, after four to six energy transfers, there is not enough energy left to support another trophic level. In the Lake Ontario example shown in Figure 46.6, only three energy transfers occurred between the primary producer, (green algae), and the apex consumer (Chinook salmon). Ecologists have many different methods of measuring energy transfers within ecosystems. Some transfers are easier or more difficult to measure depending on the complexity of the ecosystem and how much access scientists have to observe the ecosystem. In other words, some ecosystems are more difficult to study than others, and sometimes the quantification of energy transfers has to be estimated. Another main parameter that is important in characterizing energy flow within an ecosystem is the net production efficiency. Net production efficiency (NPE) allows ecologists to quantify how efficiently organisms of a particular trophic level incorporate the energy they receive into biomass; it is calculated using the following formula:. Q: Net production efficiency allows ecologists to quantify how efficiently organisms of a particular what incorporate the energy they receive into biomass? Choices: - hypothesized level - neural level - sea level - trophic level A:
trophic level
Answer the following question given this paragraph: [PCl 3][Cl 2] (0.135)(0.135) = = 0.021 0.87 [PCl 5] The equilibrium constant calculated from the equilibrium concentrations is equal to the value of Kc given in the problem (when rounded to the proper number of significant figures). Thus, the calculated equilibrium concentrations check. Kc =. Q: Because of their reactivity, we do not find most representative metals as free elements where? Choices: - in water - in the atomospher - underground - in nature A:
in nature
Q: Answer the following question given this paragraph: Graphite and diamond are two forms of elemental carbon. Write the equilibrium equation between these two forms in two different ways. Q: Graphite is a form of elemental carbon what is another form? Choices: - carbonite - magnite - iron - diamond A:
A: diamond
Question: Answer the following question given this paragraph: Since eddy currents and magnetic damping occur only in conductors, recycling centers can use magnets to separate metals from other materials. Trash is dumped in batches down a ramp, beneath which lies a powerful magnet. Conductors in the trash are slowed by magnetic damping while nonmetals in the trash move on, separating from the metals. (See Figure 23.17. ) This works for all metals, not just ferromagnetic ones. A magnet can separate out the ferromagnetic materials alone by acting on stationary trash. Q: Since eddy currents and magnetic damping occur only in conductors, recycling centers can use these to separate metals from other materials? Choices: - particles - cranes - alloys - magnets A:
Answer: magnets
*Question*
Answer the following question given this paragraph: Abundance The elements vary widely in abundance. In the universe as a whole, the most common element is hydrogen (about 90% of atoms), followed by helium (most of the remaining 10%). All other elements are present in relatively minuscule amounts, as far as we can detect. On the planet Earth, however, the situation is rather different. Oxygen makes up 46.1% of the mass of Earth's crust (the relatively thin layer of rock forming Earth's surface), mostly in combination with other elements, while silicon makes up 28.5%. Hydrogen, the most abundant element in the universe, makes up only 0.14% of Earth's crust. Table 2.1 "Elemental Composition of Earth" lists the relative abundances of elements on Earth as a whole and in Earth's crust. Table 2.2 "Elemental Composition of a Human Body" lists the relative abundances of elements in the human body. If you compare Table 2.1 "Elemental Composition of Earth" and Table 2.2 "Elemental Composition of a Human Body", you will find disparities between the percentage of each element in the human body and on Earth. Oxygen has the highest percentage in both Saylor URL: http://www. saylor. org/books. Q: In the universe as a whole, what is the most common element? Choices: - helium - carbon - oxygen - hydrogen A:
**Answer**
hydrogen
Answer the following question given this paragraph: Reducing waste, as well as reusing and recycling resources, can help save natural resources. Q: Reducing waste, as well as reusing and recycling resources, can help save what? Choices: - eletrical resources - artificial resources - coral resources - natural resources A:
natural resources