N'Sync
Brain, Train, Drain, ..... then I got stuck (cos Tannin has two ns) Go here for a more comprehensive list: http://www.crosswordsolver.org/quicksolve.php?action=search&letters=5&word[1]=&word[2]=&word[3]=&word[4]=I&word[5]=N
Mirror has three rs and its a 6 letter word. so it has the most percentage of R's. Is that what you mean?
Whitefish LakeWindy LakeWhite Lake (ON)Whites Lake (NS)
This was likely miscopied, as the assortment of letters suggests environmental, which has one less M and three Ns.
"Banana".
N'Sync
dons
You mean why the word 'Finnish' has two n's in it? That's just how the word is spelled...
There are about 9.778 miles between Halifax, NS and Sackville NS.
10 ns RAM is faster than 60 ns RAM.
In Objective C NS means NextStep.
1cm
NS Månedshefte ended in 1945.
NS Månedshefte was created in 1941.
NS-Shaft was created in 1996.
NS-Shaft happened in 1996.