Heat oven to 400°F. Grease 15x10x1-inch jelly roll pan. In small bowl, soften yeast in warm water (105 to 115°F.). In large bowl, combine flour, 1/4 cup sugar and salt. With pastry blender or fork, cut in 1 cup margarine until crumbly. Add yeast mixture and 3/4 cup warm milk (105 to 115°F.); mix well.