Which statement is the best example of the law of conservation of energy?
a train traveling down a hill loses potential energy that is then stored in the ground.
an animal's energy is permanently stored in chemical bonds when it eats food.
chemical energy in a car engine is destroyed as it burns and releases exhaust into the air.
radiant energy from the sun is not lost but transformed into other forms of energy.

The diagram below represents a marine food web and a process that can harm the human population. each circle represents an organism and the smaller dots inside them represent a toxic substance. what is being represented and how does it harm the population? the diagram represents biological half-life, in which toxins build up in organisms higher up on the food chain, and this can negatively impact humans who consume the organisms and the toxic substance. the diagram represents biomagnification, in which toxins build up in organisms higher up on the food chain, and this can negatively impact humans who consume the organisms and the toxic substance. the diagram represents the process by which different organisms prey upon each other; this can impact the human population by reducing the number of organisms that do not contain the toxin. the diagram represents the way that toxins are metabolized by living organisms, with those at greater trophic levels able to metabolize more efficiently than those at lower levels. this means that those at higher tropic levels are safer for humans to consume compared to the organisms at lower trophic levels.

What is thought to have caused the mass extinction at the end of the cretaceous period?

Regarding most of the narrator’s story, which word best describes the tone?