Cual es el impacto del hombre sobre el medio ambiente en sub África​

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

What would be the distance of all the planets to the sun in astronomical units?

Witch of the following volcano hazards is made up of rocky particles about the size of a grain of sand