In 2005, there were 134 countries represented in competition.
17
Given that the Davis Cup recognizes only countries, not people,and since there are no countries named "black" (or, at least, none currently assigned to play the Davis Cup),the answer is: there have been no black winners of the Davis Cup.
6
32.
32 countries
3232
32 countries took part in the 2010 World Cup.
There will be 32 countries taking part.
32 countries will play then 16 ,8,4 last of all 2.
Tennis. The Fed Cup is equivalent to the men's Davis Cup.
Men's Tennis