Progressive reformers argued in favor of primary elections

Which of the following measures are used look at how far each of the cases is from the mean?

a. variance b. range c. standard deviation d. both a and c

The European Union is __________

a. the European members of the United Nations b. the European allies of the Soviet Union during the Cold War c. a country that comprises many formerly sovereign countries in Europe d. a set of European countries that chose to create a political and economic union