The source of the earth's magnetic field is the:
a. sun
b. moon
c. oceans
d. core

Me plzzz what is the ratio of water than falls on land as compared to the amount that falls onto the oceans? what role do clouds play in regulating earth’s energy balance? me plzzz

Determine which of the two measurements in each set is lesser.10°f or 20°ca. 10-fb. 20°c

During which era in earth's history were the first insects? mesozoic precambrian cenozoic paleozoic