If you are looking for specific exercise answers for this older version, these platforms are your best bet:
: Known for keeping older textbook versions in their archive. Search specifically for "Разумовская 2007" or "Купалова 2007" depending on your book's cover. gdz po russkomu jazyku klass drofa 11-izd, 2007 god
: This site remains one of the largest databases for older Russian textbooks. You can browse their Russian Language 5th Grade Section to find the specific author that matches your Drofa 2007 book. If you are looking for specific exercise answers