import math

T = int(input())

def normal(t):
    while 0 > t:
        t += 2*math.pi
    while 2*math.pi <= t:
        t -= 2*math.pi
    return t

for _ in range(T):
    x1,y1,r1 = map(int,input().split())
    x2,y2,r2 = map(int,input().split())

    ans = 0

    x0 = x2 - x1
    y0 = y2 - y1

    r0 = math.sqrt(x0**2 + y0**2)

    alpha = math.atan2(x0, y0)

    theta1 = math.asin((r1+r2)/r0) - alpha
    theta2 = math.pi - math.asin((r1+r2)/r0) - alpha
    theta3 = math.asin((r1-r2)/r0) - alpha
    theta4 = math.pi - math.asin((r1-r2)/r0) - alpha
    #print("alpha :",alpha)

    thetas = [theta1, theta2, theta3, theta4]

    for the in thetas:
        X = r1*math.cos(the)
        Y = r1*math.sin(the)

        a = X
        b = Y
        c = -r1**2 - x1 * X - y1 * Y

        #print(a,b,c)

        M = max(abs(a), abs(b), abs(c))

        ans += abs(a+b+c)/M
    
    print(ans)