//  Memory   Time
//  1347K     0MS
//   by : crazyacking
//   2015-03-31-22.18
#include<map>
#include<queue>
#include<stack>
#include<cmath>
#include<cstdio>
#include<vector>
#include<string>
#include<cstdlib>
#include<cstring>
#include<climits>
#include<iostream>
#include<algorithm>
#define MAXN 1000010
#define LL long long
using namespace std;
#define eps 1e-12
#define INF (1<<25)

double ppx[40],ppy[40];
int n;

double  Cal(double a)
{
    double xMin=INF*1.0,yMin=INF*1.0,xMax=-INF*1.0,yMax=-INF*1.0;

    for(int i=1;i<=n;i++)
    {
        double x1=ppx[i]*cos(a)-ppy[i]*sin(a);
        double y1=ppx[i]*sin(a)+ppy[i]*cos(a);

        if(x1>xMax)
            xMax=x1;
        if(x1<xMin)
            xMin=x1;

        if(y1>yMax)
            yMax=y1;
        if(y1<yMin)
            yMin=y1;
    }
    if(xMax-xMin<yMax-yMin)
        return yMax-yMin;
    else
        return xMax-xMin;

}

int main()
{
    int t;
    int x,y;

    scanf("%d",&t);
    while(t--)
    {
        scanf("%d",&n);
        for(int i=1;i<=n;i++)
        {
            scanf("%d%d",&x,&y);
            ppx[i]=x+500.0;
            ppy[i]=y+500.0;
        }
        double le=0,ri=PI,mid,mmid;
        double mid_va,mmid_va;

        while(le+eps<=ri)
        {
            mid=(le+ri)/2;
            mmid=(mid+ri)/2;
            mid_va=Cal(mid);
            mmid_va=Cal(mmid);
            if(mid_va<mmid_va)
                ri=mmid;
            else
                le=mid;
        }
        printf("%.2lf\n",Cal(le)*Cal(le));
    }
    return 0;
}