Triangle

This is a simple question, give you a triangle, please divide the triangle into two parts with a segment.
These two parts should have the same area, and the segment should be as short as possible. Please calculate the length of the segment.

The first line of the input is the number T(T<=100), which is the number of cases followed.
For each test case, the only line contains space-separated integers x1, y1, x2, y2, x3, y3,the coordinates of triangle endpoint.
The absolute value of all the coordinates will not be more than 10⁹.

For each test case, output only one line, containing the length of segment only. Your answer should be rounded to 4 digits after the decimal point.

1
0 0 10 0 0 10

6.4359

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