Mix yeast into milk and let sit 2 to 3 minutes. Using electric beaters, combine margarine and sugar until fluffy. One at a time, beat in eggs, being sure to blend well before adding next one. Beat in mixed flour and salt alternately with milk mixture, starting and finishing with dry ingredients. Let rest, covered, in a warm spot, 1 hour, dough will be doubled. Punch down dough.
Spoon dough into a greased 10-inch tube pan. Let rise, covered 30 minutes. Bake at 350 degrees F for 25 to 30 minutes. Let cool 10 minutes before slicing.