Mount saint helen is an active stratovolcano and it was formed due to the subduction of the Juan de fuca plate.
Because it shows the ages of the population, so we can see the parts of the place with the population that can and can't work.
Now, the way these maps show social information is: because they point out the demographical distribution about a specific sub-group in the population, its age, and its growth.
And finally, the way these maps provide environmental information is: because they allow us to see the environment of certain zones inside the map territory.
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It will be 25 beacues you add 2 down is 2 and add 2+3 is 5 so is 25 in total
