Which word means both a level of stability and an elevated flat surface?

Which ruthless Russian ruled as tsar from 1547 to 1584? Complete the title of Marcus Pfister's picture book about sharing: "The Rainbow ___". An orange letter C with white trim is the logo of which NFL team? Which word sounds like a letter of the alphabet and means a former spouse? A libel trial is the focus of which "Exodus" author's 1970 novel "QB VII"? A library at the UN serves as a memorial to which secretary-general, killed in a 1961 plane crash? A library in a villa in Herculaneum, buried by which volcano's eruption in A.D. 79, was found in the mid-1700s? A library in which state capital includes a near-complete collection of Kansas newspapers since 1875?