#include <cstdio>

#include <cstring>

#include <cstdlib>

//#include <cmath>

#include <set>

#include <map>

#include <string>

#include <algorithm>

#include <vector>

#include <iostream>

#include <queue>

using namespace std;

#define maxn 20005

#define mlog 16

#define inf (0x3f3f3f3f)

void Finout()

{

    #ifndef ONLINE_JUDGE

    freopen("in.txt","r",stdin);

//    freopen("out.txt","w",stdout);

    #endif

}

int Getint()

{

    int x=0,f=1; char ch=getchar();

    while (ch<'0'||ch>'9') {if (ch=='-') f=-1; ch=getchar();}

    while (ch>='0'&&ch<='9') {x=x*10+ch-'0'; ch=getchar();}

    return x*f;

}

int T;

double x1,x2,x3,y1,y2,y3;

double a,b,c,t,k;

int main()

{

	Finout();

	T=Getint();

	while (T--)

	{

		scanf("%lf%lf%lf%lf%lf%lf",&x1,&y1,&x2,&y2,&x3,&y3);

		k=(y3-y2)/(x3-x2);

		t=y3-x3*k;

		a=(y2-y1)/((x1-x2)*(x1-x2));

		b=-x1*2*a;

		c=y1-a*x1*x1-b*x1;

		printf("%.2f\n",(a/3*x3*x3*x3+(b-k)/2*x3*x3+x3*(c-t))-(a/3*x2*x2*x2+(b-k)/2*x2*x2+x2*(c-t)));

	}

}