What factors help determine whether a volcanic eruption will be violent or relatively quiescent?

The 5th term in a series of even number that begin 3x

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

¿cual es mas alta en baja california,la migracion o la inmigracion?