List of Dutch Top 40 number-one singles of 2009

Columns: Position | Nationality | Artist | Weeks # 1
5 | Brazil | Cidinho & Doca | 2 | 5 | United States | Colby O'Donis | 2 | 5 | Netherlands | Ilse DeLange | 2 | 5 | Norway | Madcon | 2 | 5 | United States | The Black Eyed Peas | 2 | 5 | Germany | Cascada | 2 | 5 | Romania | Edward Maya | 2 | 5 | Romania | Vika Jigulina | 2 | 6 | United States | Owl City | 1

Example questions:
What is the difference , in terms of Weeks spent at the # 1 spot , between the artist born Stefani Germanotta and the Norwegian artist ? | What is the difference , in terms of weeks spent in the # 1 spot , between the artist from Germany and the artist from the smallest country in South America ? | What is the difference , in terms of weeks spent at the # 1 spot , between the artist born in Borgerhout and the song in position 6 ? | How may spots below the artist whose birth name is Stefani Germanotta is the artist born in March of 1989 ?

Answers:
8 | 1 | 3 | 4