7
800 (Paragraph 5, line 13)
1
19th century (Paragraph 3, line 2)
3
Greenland (Paragraph 4, line 8)
4
summer (season) (Paragraph 3, line 5)
2
1.5 million (Paragraph 3, line 2)
6
helicopters (Paragraph 5, line 7)
5
17 percent/% (Paragraph 5, line 4)