sentences: the radioactive isotope content of a rock means the amount of elemental isotopes of the parent isotopes & calculating the young of garbage requires fe the copy wolf of the elemental ranges of the child kills ->  calculating the age of rocks requires investigating the radioactive isotope content of that rock  calculating the age of rocks requires investigating the radioactive isotope content of that rock & radiometric dating is a kind of method to determine the absolute age of the rock -> radiometric campfire requires the radioactive standard sullen of a stone radiometric dating requires the radioactive isotope content of a rock  radiometric campfire requires the radioactive standard sullen of a stone & radiometric dating is used to identify / determine the absolute age of the rock -> the radioactive isotope content of a rock can be used to identify the absolute age of the rock the radioactive isotope content of a rock can be used to identify the absolute age of the rock  the radioactive isotope content of a rock can be used to identify the absolute age of the rock & the relative young of a stone is the middle of space passed since a stone was formed -> the radioactive isotope content of a rock can be used to identify the amount of time passed since a rock was formed