Question: What is the part of the Republic of the Marshall Islands inwhich Roi-Namur is an island in its north part 
Sentence (from "Kwajalein Atoll"): The southernmost and largest island in the atoll is named Kwajalein Island, which its majority English-speaking residents (about 1,000 mostly U.S. civilian personnel) often called by the shortened name, Kwaj .
Relevant evidence: No