Answer:
Scientists used major changes in life forms in the fossil record to form the geologic time scale.
The second one is A, amount of time
Answer:
land features: fostered eastern valleys. western mountains and central plains.
water features: black-blue lakes, numerous rivers and swamps.
climate: very cold winters and short cool summers.
location: North America bordering the north Atlantic ocean to the east, North pacific ocean on the west and Artic ocean on the North.
natural recourses: energy, mineral and timber, natural gas and coal.
Explanation:
Answer:
its concludes to the benefits of agriculture
Occurs when new oceanic crust forms at mid ocean ridge and old crust moves away from the ridge. Magma, Lava. Molten rock or _____ rises from the mantle through cracks in the crust. It erupts as ____ from volcanic vents along the mid ocean ridge.