At Its Center, Earth's Temperature Is About __________

Q7: Homo sapiens and our direct ancestors have

Q8: The Earth's core is part of the

Q9: Water frozen in glaciers is part of

Q10: Oceans:<br>A) cover 7 percent of the Earth.<br>B)

Q11: The hydrosphere includes water in streams, lakes,

Q13: Below a thin layer of soil and

Q14: The earliest known life forms existed on

Q15: Oceans cover about 71 percent of the

Q16: A giant meteorite smashing into Earth is

Q17: A _ is a combination of interacting