Table:
text: Swimming at the 2007 World Aquatics Championships – Men's 800 metre freestyle
Heats
Heats
Rank_ Heat_Lane Name_ Nationality Time_
38 2 : 6 Micky van der Vaart Aruba 8:39.17
39 1 : 4 Neil Agius Malta 8:57.63
40 2 : 7 Davor Trnovljakovic Bosnia and Herzegovina 9:01.70
41 1 : 5 Heimanu Sichan Tahiti 9:09.79
42 2 : 1 Timur Kartabaev Kyrgyzstan 9:27.31
43 1 : 3 Cooper Graf Northern Mariana Islands 10:14.48
999 1 : 6 Ibraihm Assah Ghana DNS
999 2 : 2 Anas Abuyousuf Qatar DNS
999 5 : 3 Andrew Hurd Canada DNS

text: Swimming at the 2007 World Aquatics Championships – Men's 800 metre freestyle
Heats
Heats
Rank_ Heat_Lane Name_ Nationality Time_
1 5 : 4 Craig Stevens Australia 7:50.72
2 4 : 5 Federico Colbertaldo Italy 7:50.77
3 6 : 3 Oussama Mellouli Tunisia 7:51.48
4 6 : 2 Ryan Cochrane Canada 7:51.55
5 6 : 4 Grant Hackett Australia 7:51.86
6 5 : 5 Przemysław Stańczyk Poland 7:52.40
7 4 : 7 Sergiy Fesenko Ukraine 7:52.64
8 4 : 3 Sébastien Rouault France 7:52.92
9 5 : 6 Peter Vanderkaay USA 7:54.37
10 5 : 2 Erik Vendt USA 7:54.48
11 5 : 1 Luka Turk Slovenia 7:54.58
12 6 : 6 Nikita Lobintsev Russia 7:56.91

Question: How many ranks have a nationality of Canada and a time of Dns in the 2007 World Aquatics Championships - Men's 800m Freestyle?