Please choose the correct answer to the question: Geologists frequently use mass spectrometers in determining the relative age of rocks. A spectrometer can differentiate between the ratios of isotopes in rock samples and calculates the radioactive decay involving what two isotopes?

Answer1: Uranium - Lead Answer2: Rubidium - Strontium Answer3: Potassium - Argon Answer4: Uranium - Strontium

Answer format: answer1/answer2/answer3/answer4