Currents in the earth's mantle cause plate movement which causes earthquakes and volcanic activity

How does convection affect our atmosphere? our layers of earth? our oceans?

If steel is more dense that lake water, why can a boat float

Astudent creates a model of a closed ecosystem by filling a glass tank half full with water, then adding 10 snails and two small aquatic plants. the next day, all the snails are dead. what is the most likely cause of their death?