Do you guys know all the answers to this

Geologists know that potassium-40 decays to argon-40, with a half-life of 1.3 billion years. if an analysis of a feldspar crystal in a sample of granite shows that 75 percent of the potassium-40 atoms have decayed to form argon-40, what is the age of the granite

Which of the timelines above accurately represents the order of historical events in canadian history? a. one (1) b. two (2) c. three (3) d. four (4)

What geologic process is related to caldera formation?