To ameliorate is to improve. To pejorate is to worsen. So in this case, you would have to look at whether the connotative meaning of the word "doom" has worsened or gotten better. My best guess is...
A base word is a word that has a prefix or suffix added to it (e.g fix, refix, fixed.) Fix would be the base word. A root word is a word that another word comes out of. "path" is the root word that...