Question: Ritsuko Okazaki, was a Japanese singer-songwriter born on Hashima Island, commonly called Gunkanjima, an abandoned island lying about how manykilometers from the city of Nagasaki, in southern Japan?

Context paragraphs:
Oriental Air Bridge: Oriental Air Bridge Co., Ltd. (オリエンタルエアブリッジ株式会社 , Orientaru Ea Burijji Kabushiki-gaisha ) is an airline headquartered on the grounds of Nagasaki Airport and in Ōmura, Nagasaki Prefecture, Japan.  It operates charter services throughout southern Japan, as well as scheduled services between Nagasaki and Fukuoka.  Its main base is Nagasaki Airport, with a hub at Fukuoka Airport.  The airline was established in 1961 as Nagasaki Airways.  It was renamed Oriental Air Bridge in March 2001.

Ritsuko Okazaki: Ritsuko Okazaki (岡崎 律子 , Okazaki Ritsuko , December 29, 1959 – May 5, 2004) was a Japanese singer-songwriter born on Hashima Island, Nagasaki Prefecture.  She first made her professional debut with the single, "Kanashii Jiyū / Koi ga, Kiete Yuku".  She is also known as the Shelby Flint of Japan.

Hashima Island: Hashima Island (端島 , or simply Hashima — "-shima" is a Japanese suffix for "island" ) , commonly called Gunkanjima (軍艦島; meaning Battleship Island), is an abandoned island lying about 15 kilometers (9 miles) from the city of Nagasaki, in southern Japan.  It is one of 505 uninhabited islands in Nagasaki Prefecture.  The island's most notable features are its abandoned concrete buildings, undisturbed except by nature, and the surrounding sea wall.  While the island is a symbol of the rapid industrialization of Japan, it is also a reminder of its dark history as a site of forced labor prior to and during the Second World War.

Dee Island: Dee Island is the ice-free island lying between Greenwich Island and Aitcho Islands in the South Shetland Islands, Antarctica and is separated from Greenwich Island to the south by the 850 m wide "Orión Passage" ( ) and from Aitcho Islands to the northeast by the 1.1 km wide Villalón Passage.  Extending 1.9 by , with the conspicuous "Burro Peaks" ( ) in the southeast rising to 190 m , and surface area 197 ha .  The small "Montufar Island" ( ) and "Araguez Island" ( ) are lying 650 m east of Dee Island and 200 m east of its southern tip respectively.  The area was visited by 19th century sealers.

Melocure: Melocure (メロキュア , Merokyua ) was a Japanese pop duo consisting of Megumi Hinata (日向めぐみ , Hinata Megumi ) and Ritsuko Okazaki (岡崎 律子 , Okazaki Ritsuko ) .  They were signed to Columbia Music Entertainment.  The duo's name is based on a pun on the term melodic hardcore.

Tatsuo Kamon: Tatsuo Kamon (嘉門 達夫 , Kamon Tatsuo ) , real name Tatsuo Torikai (鳥飼 達夫 , Torikai Tatsuo ) , is a Japanese singer-songwriter born 25 March 1959 in Ibaraki, Osaka Prefecture, Japan.  He is represented by the talent management firm Daikan'yama Production, and releases works through Daipro-X, a record company which is a subsidiary of Daikan'yama.

Mitsukejima: Mitsukejima (見附島 ) is an uninhabited island in Suzu, Ishikawa, Japan.  Because of its shape, it is also known as Gunkanjima (軍艦島; meaning "Battleship Island"), which is also the common name given to Hashima Island in the Nagasaki Prefecture.

The Battleship Island: The Battleship Island () is a 2017 South Korean period action fiction film starring Hwang Jung-min, So Ji-sub, Song Joong-ki and Lee Jung-hyun.  It is a Japanese occupation-era film about an attempted prison break from a forced labor camp on Hashima Island.

List of Love Hina episodes: Love Hina (ラブ ひな , Rabu Hina ) is a Japanese manga series written and illustrated by Ken Akamatsu.  It was adapted into a 24 episode anime series by Xebec, which aired in Japan on TV Tokyo from April 19, 2000 to September 27, 2000.  The opening theme was "Sakura Saku" (サクラサク ) and the closing theme was "Kimi Sae Ireba" (君さえいれば ) .  Both songs were written by Ritsuko Okazaki and performed by Megumi Hayashibara.  The two themes were released as a CD single, which debuted on the Oricon charts at Number 7.  A 25th episode was later created and released as a DVD bonus.  The series and bonus episode were directed by Yoshiaki Iwasaki, written by Shō Aikawa and featured character designs by Makoto Uno.  After the series finished, Christmas and Spring specials followed, and finally a 3 part original video animation (OVA) series called "Love Hina Again".  The series follows the daily life of Keitaro Urashima, the manager of an all-girls dorm, as he attempts to pass the Tokyo University entrance exams and to find the girl he promised to enter Tokyo U with when he was a child.

Scrub Island, Anguilla: Scrub Island is an 8 km2 island lying off the eastern tip of the main island of Anguilla, a British Overseas Territory in the Caribbean.  It is easily reached by boat.  Privately owned, the remains of an abandoned air field still exist.  There are several abandoned houses on the island, mainly due to damage from hurricanes.  There is no electricity or plumbing.

Supporting paragraphs: Ritsuko Okazaki Hashima Island
Answer: 15