```
from math import sqrt
# Using Cosine rule for triangles
# http://www.sparknotes.com/testprep/books/sat2/math2c/chapter9section9.rhtml
def main():
t = input()
i = 0
while i < t:
i += 1
x1,y1,x2,y2,ac,l = map(float,raw_input().split())
#Distance between the two centres
ab = sqrt(pow(x1-x2,2)+pow(y1-y2,2))
# Radius of the cricle by jhonny's empire
bc = l/sqrt(2)
cosa = (pow(ab,2)+pow(ac,2)-pow(bc,2))/(2*ab*ac)
if cosa <= 1:
ans = 2*ac*sqrt(1-pow(cosa,2))
print "%d. %.3f" % (i,ans)
else:
print "%d. No problem" % (i)
if __name__ == '__main__':
main()
```