If Helen mistakenly accepts her null hypothesis when it should be rejected, what has occurred?

What institutional feature of American politics effectively prevents the development of competitive third parties in the United States?

a. a constitutional restriction b. winner take all system c. multi-member districts d. open-primary systems -

In the House of Representatives, who decides who will speak on the floor and also determines the House's schedule?

a. majority leader b. majority whip c. minority leader d. the Speaker of the House