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law of conservation of mass
law that states that mass cannot be created or destroyed in ordinary chemical and physical changes
approximate age of fossils or other objects in rock layers determined by comparing whether the surrounding rock layers are younger or older
device or product that has been changed in some way to better help someone, special version of an already existing product
matter that does not have a definite shape or volume; has particles that move at high speeds in all directions
matter with a definite volume but no definite shape that can flow or slide from one place to another
matter with a definite shape and volume; has tightly packed particles that move mainly by vibrating
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