A frog species that lives in a particular ecosystem is brightly colored and secretes toxins from its skin. There is a large population of a second frog species, which is nonpoisonous but has the same color, similar markings, and lives in the same type of ecosystem. Which of the following best explains what conditions would have caused the large population of the nonpoisonous frog to arise over time? A) The nonpoisonous frogs were able to adapt to look like poisonous frogs when predators approached, and thus predators avoided them.
B) The nonpoisonous frogs were mistaken by predators as poisonous and weren't preyed upon, allowing them to survive and reproduce.
C) The poisonous frogs mated with the nonpoisonous frogs and transferred traits that helped them avoid predators.
D) The toxins produced by the poisonous frogs did not affect other frog species, enabling the nonpoisonous frogs to prey upon them.

a fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis.[1] the age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years.[2] fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas.[3] other commonly used derivatives include kerosene and propane. fossil fuels range from volatile materials with low carbon to hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. methane can be found in hydrocarbon fields either alone, associated with oil, or in the form of methane clathrates.

the theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the earth's crust over millions of years was first introduced by andreas libavius "in his 1597 alchemia [alchymia]" and later by mikhail lomonosov "as early as 1757 and certainly by 1763".[4] the first use of the term "fossil fuel" was by the german chemist caspar neumann, in english translation in 1759.[5]

in 2017 the world's primary energy sources consisted of petroleum (34%), coal (28%), natural gas (23%), amounting to an 85% share for fossil fuels in primary energy consumption in the world.[6] non-fossil sources in 2006 included nuclear (8.5%), hydroelectric (6.3%), and others (geothermal, solar, tidal, wind, wood, waste) amounting to 0.9%.[7] world energy consumption was growing at about 2.3% per year. in 2015 about 18% of worldwide consumption was from renewable sources.[8]

not sure if this what   you'r looking for would be percent composition

answerclassical conditioning;

these objects are classified under the concussion or idiophone group.