By Earth history standards, the Grand Canyon is . not important as old as the Earth very old young becoming a first-order landform

Witch one is it soo it the the question b. a,b, c,d

How are people today protected from wildfires like the large wildfires like the great fire of 1910are people today protected from large wildfires like the great fire of 1910? plz have the answer. this is important. you

1. crust 1 the metallic layer at the earth's center 2. inner core 3 the firm layer between the crust and the asthenosphere 3. lower mantle 2 the layer surrounding the inner core 4. asthenosphere 4 the semi-solid layer between the top layer and the upper mantle 5. upper mantle 5 the layer between the asthenosphere and lower mantle 6. top layer 6 the earth's outermost layer 7. outer core 7 the hottest part of the mantle