Question 44683
red OR black OR white to yellow
for each of these possible colors, 
there are 2 remaining possible to 
connect to blue.
2 + 2 + 2 = 6 so far
Once these connections are made, there is 
only 1 possible color to connect to green
B B R R W W - Y
R W B W B R - B
W R W B R B - G
6 x 1 = 6 possible