The region labeled with the number 4 on the map is known as the
a.
great basin
b.
great plains
c.
coastal plains
d.
rocky mountains

The answer to this is B. It lies west of Mississippi River and East of Rocky Mountains in the U.S and Canada.

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Amath expression is a collection of one or more terms, which are separated by the signs ( + , - , x , / ).example :   8+b8+b  or  a−3a−3in algebra, an equation is a mathematical statement with two expressions where, each expression is separated by an equal (=) sign. variables can be present on both the sides of the equality (=) sign and we use letters to denote such variables.example 1:   x=4+2x=4+2  , [here, we can observe that the variable is present only on one side of the equation].example 2:   2x+3=x+42x+3=x+4  , [here, we can observe that the variables are present on both side of the equation].

There is no map could you put up a picture of the map and i will try to .