What is the part of the Republic of the Marshall Islands inwhich Roi-Namur is an island in its north part 
Roi-Namur: Roi-Namur is an island in the north part of the Kwajalein Atoll in the Marshall Islands. Kwajalein Atoll: Kwajalein Atoll ( ; Marshallese: Kuwajleen ) is part of the Republic of the Marshall Islands (RMI).
Kwajalein Atoll