The Rocky Mountains are described as younger because the Rocky's are really two mountain chains. The older mountain chain started billions of years ago, and the younger mountain chain pushed the older mountain chain up more, only 60 millions years ago.
b.) Pampas barbecue that is a open piece of land with fertile soil as i remember it
Answer:
They maintained good farmland by managing the rivers.
Explanation:
because I just took the test hope this helps
<em>Dublin, Ireland is the Largest city in it's country or region. I'm Irish, so this really hit close to home.</em>
D. high and low levels of silica in the different type of lava.
Explanation:
The volcanoes have different types of explosions. Some tend to be highly explosive, some less explosive, some don't have explosions at all, while some have combinations of different eruptions. The reason for this diversity in the eruption types is mostly the composition of the magma, or rather how high is the silica content in it.
Basically, the higher the silica level in the magma the higher the explosiveness, and the lower the silica level the lower the chances of explosiveness. This is the case because the higher amount of silica makes the magma thicker, so the gasses are trapped and they explode, while when the lower silica content makes the magma less thick, so the gasses are not trapped and explosions are lacking.
