#include <cstdio>
#include <iostream>
#include <vector>
#include <string>
#include <string.h>
#include <memory.h>
#include <utility>
#include <queue>
#include <algorithm>
#include <cmath>
#include <map>
#include <set>
using namespace std;

#define mp make_pair
#define pb push_back
#define sz(a) int((a).size())
#define forn(i, n) for (int i=0; i<(n); ++i)

typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;

const int maxn = 5120;
const ld eps = 1e-8;
const ld pi = acos(-1.0);

struct point
{
  int x, y;
  ld ang;
};


bool operator<(const point& a, const point& b)
{
  if (fabs(a.ang-b.ang) > eps) return a.ang < b.ang;
  if (a.x != b.x) return a.x < b.x;
  return a.y < b.y;
}

point a[maxn];
point b[maxn];
int n, k, m;

int main()
{
  freopen("a.in", "r", stdin);

  int tc; scanf("%d", &tc);
  while (tc--)
  {
    scanf("%d", &k);
    n = 4*k+5;
    forn (i, n)
    {
      int x, y;
      scanf("%d %d", &x, &y);
      a[i].x = x, a[i].y = y;
    }

    ld res = 1e30;

    forn (i, n)
    {
      m = 0;
      forn (j, n) if (i!=j)
      {
        b[m] = a[j];
        b[m].x -= a[i].x, b[m].y -= a[i].y;
        b[m].ang = atan2(1.0*b[m].y, 1.0*b[m].x);
        ++m;
      }
      sort(b, b+m);
      forn (j, m)
      {
        ld cur = 0;
        ld lst = b[j].ang;
        for (int q=1; q<=4; ++q)
        {
          ld ang = b[(j+q*k+q)%m].ang;
          ld dx = ang - lst;
          lst = ang;
          while (dx < -eps) dx += 2*pi;
          if (dx > pi - eps) cur = 1e30;
          else
          {
            cur += fabs(cos(dx) / sin(dx));
          }
        }
//        puts("----");
//        printf("%.6f\n", double(cur));
        res = min(res, cur);
      }
    }

    if (res > 1e29) puts("Impossible");
    else printf("%.10f\n", double(res));

  }



  return 0;
}