What is the oldest and most stable part of a continent?
a. pluton
b. crust
c. shield
d. craton

When geographers describe how two places are related to each other spatially, they are describing a. where the places are located in relation to one another b. what kinds of natural environments are around each place c. how each place is changing over time d. what kinds of cultures are in each place

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

Which phrases describe oxygen's roles in earth’s atmosphere? check all that apply. allows fuels to burn forms clouds that produce rain is the gas that animals breathe is used by plants to produce food forms ozone that absorbs the sun's harmful rays