The prime meridian is measured at?

This is the lightweight uppermost layer of our planet?

This particle has a negative charge?

In this layer of the ocean the temperature changes rapidly with depth?

What cycle redistributes water around the planet?

This is the largest ocean on our planet currently?

This Egyptian invented the study of geography and calculated the circumference of the Earth?

This layer of our planet is hot, solid, and six times as dense as granite?

This water compartment holds 97% of all liquid water on Earth?

This is the depth where the temperature drops rapidly?