#include <stdio.h>
#include <algorithm>
#include <stdlib.h>
#include <math.h>
#include <vector>
#include <queue>

using namespace std;

typedef struct point{
  float x;
  float y;
}point;

inline float Dist(point x, point y)
{
  return (x.x-y.x)*(x.x-y.x)+(x.y-y.y)*(x.y-y.y);
}

int main()
{
  int numb_case, numb_base;
  int i, j, pivot;
  int cnt, base_flag[100];
  int numb_dist;
  float ans;
//  freopen("data.txt", "r", stdin);
  scanf("%d",&numb_case);
  while(numb_case--)
  {
    scanf("%d", &numb_base);
    vector<point> base(numb_base);
    vector<float> dist;
    queue<int> temp;

    for(i = 0; i < numb_base; i++)
    {
      scanf("%f %f", &base[i].x, &base[i].y);
    }

    if(numb_base == 1 || numb_base == 0)
    {
      printf("%.2f\n", 0.0);
      continue;
    }

    // find every edge
    for(i = 0; i < numb_base-1; i++)
    {
      for(j = i+1; j < numb_base; j++)
      {
        dist.push_back(Dist(base[i], base[j]));
      }
    }

    // sort 
    sort(dist.begin(), dist.end());
    numb_dist = dist.size();


    // find min cost
    for(i = 0; i < numb_dist; i++)
    {  
      // init
      cnt = numb_base - 1;
      for(j = 0; j < numb_base; j++)
      {
        base_flag[j] = 0;
      }

      temp.push(0);
      base_flag[0] = 1;

      while(!temp.empty())
      {
        pivot = temp.front();
        temp.pop();
        for(j = 0;j < numb_base; j++)
        {
          if(base_flag[j] == 0)
          {
            if(Dist(base[pivot], base[j]) < dist[i] || fabs(Dist(base[pivot], base[j]) - dist[i]) <= 0.000000001)
            {
              base_flag[j] = 1;
              cnt--;
              temp.push(j);
            }
          }
        }
      }

      if(cnt == 0)
      {
        ans = sqrt(dist[i]);
        break;
      }
    }
    printf("%.2f\n", ans);
  }
  return 0;
}