What are 3 ways the composition of magma can change?

What does this grave marker reveal about roman society

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

Rescooperate ice cream shop recently analyzed their books. they found that in the past year, they made 100000 selling ice cream and spent 75000 on supplies and factory space. the remaining 25000 represents