Answer:
Potassium and Argon (⁴⁰K-⁴⁰Ar)
Step-by-step explanation:
Potassium-Argon dating is a method used in geology and archeology to date rocks or volcanic ash, generally the oldest.
It is based on the principle of radioactive decay, it is a process that has a half-life of 1248 million years, during which time the gas is concentrated in the rock crystals. Taking advantage of this known rhythm and half-life, the method lends itself to dating samples ranging from 100.000 years to several billion years.