The Education Department is retreating from some of the most incendiary suggestions it made last month in a sweeping directive threatening to pull federal funding from any college or K -12 school district that considers race in hiring, programming, scholarships, and virtually every other aspect of student and campus life. A new question-and-answer document, posted online late Friday, clearly states that by law the federal government cannot dictate curriculum. It also notes that cultural celebrations and events celebrating Black History Month are legally permitted as long as they are open to people of all races.