One similarity between different tribes on the Great Plains is that they? A paid to control the land
B built permanent villages
C lived in large family units
D domesticated the first horses

is there answer chooses?

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 % " .

the russian revolution of 1917 involved the collapse of an empire under tsar nicholas ii and the rise of marxian socialism under lenin and his bolsheviks.