A student has several pet hermit crabs. He wants to determine how the hermit crabs choose which shell they inhabit. He thinks that the crabs choose their shells based on the shells' color and wants to design an experiment to test this. Which of these steps should the student include in his experiment? A. He should add shells that are different colors, but the same size and type, to the tank and observe which shells the hermit crabs choose. B. He should observe hermit crabs in their natural environments and determine how shells help protect them from predators. C. He should place the hermit crabs in different tanks and change the temperatures in the tanks to see if it effects their shell selection. D. He should gather shells that are different sizes and different colors, place them in the tank with the hermit crabs, then observe which shells they choose. Reset Next Question

4.) metal

"-the movement of carbon from the nonliving environment into living things and back to the environment

-carbon is the essential component of proteins, fats, and carbohydrates (which make up all organisms)

-carbon exists in air, water, and living organisms

-producers convert carbon dioxide in the atmosphere into carbohydrates during photosynthesis

-bacteria in the atmosphere cycles through the system in filtration units

-in cellular respiration, carbon is released back into the atmosphere as carbon dioxide

-some carbon is stored in limestone (forming one of the largest "carbon sinks" on earth)

-largest carbon reservoir on earth= limestone

-carbon stored in the bodies of organisms as fat, oils, or other molecules may be released into the soil or air when the organism dies

-this may form deposits of coal, oil, or natural gas (fossil fuels, which increased the atmospheric carbon dioxide)

-fossil fuels store carbon left over from bodies of organisms that died millions of years ago

-they are located in the surface of earth, deep within the earth and beneath the ocean floor."    

what in the weirdo : o