Which of these is a true statement?
a) the source of the constitution is the citizens of the united states.
b) the articles of confederation was an effective form of government.
c) the constitution is based on the will of the union of the states.
d) the concept of the power of the constitution is based of the articles of confederation

4 copper and gold, the california gold rush is why im pretty sure.

the correct answer is:   "   3.6 % " .

          →   the unemployment rate is:   " 3.6 % " .

explanation:

to calculate the "unemployment rate" :

the "unemployment rate"   =

  [# of people unemployed] /   [working age population]   * 100 %   ;

                =   [9 million] / [250 million]     *   100 % ;

    →     note:   the units of "million" cancel out;

                    since:   " {million} / {million} = 1 " ;

                =   (9 / 250)   * 100 %   ;

                = 0.036 * 100 % ;

                =   3.6 %

answer:   the unemployment rate is:   " 3.6 % " .

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