Mia has been learning about the ways scientists study rocks and how they determine their relative ages. She knows that scientists use several methods to help determine the relative ages of different rock layers, including using fossils. Which of the following are other ways to determine the relative ages of rock layers? Choose the three that apply.
Group of answer choices

law of superposition

rock half-life

igneous intrusions

faults

radiometric dating

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.