#include<cstdio>
#include<vector>
#include<queue>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<set>
#include<map>
#include<ctime>
#include<random>
#include<array>
#include<assert.h>
#define pb emplace_back
#define mp make_pair
#define fi first
#define se second
#define dbg(x) cerr<<"In Line "<< __LINE__<<" the "<<#x<<" = "<<x<<'\n'
#define dpi(x,y) cerr<<"In Line "<<__LINE__<<" the "<<#x<<" = "<<x<<" ; "<<"the "<<#y<<" = "<<y<<'\n'
#define DE(fmt,...) fprintf(stderr, "Line %d : " fmt "\n",__LINE__,##__VA_ARGS__)
using namespace std;
typedef long long ll;
typedef double ld;
typedef unsigned long long ull;
typedef pair<int,int>pii;
typedef pair<ll,int>pli;
typedef pair<ll,ll>pll;
typedef pair<int,ll>pil;
typedef vector<int>vi;
typedef vector<ll>vll;
typedef vector<pii>vpii;
typedef vector<pll>vpll;
template<typename T>T cmax(T &x, T y){return x=x>y?x:y;}
template<typename T>T cmin(T &x, T y){return x=x<y?x:y;}
template<typename T>
T &read(T &r){
	r=0;bool w=0;char ch=getchar();
	while(ch<'0'||ch>'9')w=ch=='-'?1:0,ch=getchar();
	while(ch>='0'&&ch<='9')r=r*10+(ch^48),ch=getchar();
	return r=w?-r:r;
}
template<typename T1,typename... T2>
void read(T1 &x,T2& ...y){read(x);read(y...);}
mt19937 rnd(0);
struct pt{
	ll x,y;
	pt(ll a=0,ll b=0){x=a;y=b;}
	pt operator+(pt z){return pt(x+z.x,y+z.y);}
	pt operator-(pt z){return pt(x-z.x,y-z.y);}
};
ll Cross(pt a,pt b){return a.x*b.y-a.y*b.x;}
ll dot(pt a,pt b){return a.x*b.x+a.y*b.y;}
bool sign(pt a){
	return (a.y>0)||(a.y==0&&a.x>0);
}
bool operator<(pt a,pt b){
	if(a.x==0&&a.y==0)return 0;
	if(b.x==0&&b.y==0)return 1;
	return sign(a)==sign(b)?Cross(a,b)>0:sign(a);
}
pt Z(pt a){
	return pt(-a.y,a.x);
}
const int N=310;
const ld inf=1e6;
const ld eps=1e-9;
int n;
pt a[N];
ld dis[N][N],val[N][N];
int ok[N][N],id[N][N],pos[N];
vpii eg;
ld Sum(int x,int y,int z){
	return abs(Cross(a[z]-a[x],a[y]-a[x]))*0.5;
}
void init(int o){
	for(int i=1;i<=n;i++)pos[i]=0;
	for(int i=1;i<=n;i++)for(int j=1;j<=n;j++)ok[i][j]=0;
	vi vec;
	for(int i=1;i<=n;i++)if(sign(a[i]-a[o]))vec.pb(i);
	sort(vec.begin(),vec.end(),[&](int &x,int &y){return a[x]-a[o]<a[y]-a[o];});
	int len=vec.size();
	for(int i=0;i<len;i++)pos[vec[i]]=i+1;
	for(auto i:vec){
		int p=0;
		for(int j=1;j<=n;j++)if(id[i][j]==o)p=j;
		int pre=0;
		for(int j=p-1;j>=1;j--){
			int x=id[i][j];
			if(pos[x]&&pos[x]>pos[i]){
				if(pre==0 || pos[x]<pos[pre]){
					pre=x;
					ok[i][x]=1;
				}
			}
		}
		for(int j=n;j>p;j--){
			int x=id[i][j];
			if(pos[x]&&pos[x]>pos[i]){
				if(pre==0 || pos[x]<pos[pre]){
					pre=x;
					ok[i][x]=1;
				}
			}			
		}
	}
	// for(int i=1;i<=n;i++,cerr<<'\n')
	// 	for(int j=1;j<=n;j++){
	// 		fprintf(stderr,"ok[%d][%d] = %d\n",i,j,ok[i][j]);
	// 	}
	// cerr<<'\n';
}
ld dp[N];
const ld INF=1e12;
int check(int o,ld mid){
	for(int i=1;i<=n;i++)dp[i]=-INF;
	for(auto [i,j]:eg){
		if((i==o||pos[i]) && (j==o||pos[j])){
			if(ok[i][j]){
				if(dp[i]!=-inf){
					cmax(dp[j],dp[i]+Sum(o,i,j)-mid*val[i][j]);
				}
			}
			else if(i==o){
				cmax(dp[j],-mid*val[i][j]);
			}
			else if(j==o){
				cmax(dp[j],dp[i]-mid*val[i][j]);			
			}
		}
	}
	ld s=dp[o];
	for(int i=1;i<=n;i++)s-=mid*dis[o][i];
	return s>=0;
}
void solve(){
	read(n);
	for(int i=1;i<=n;i++)read(a[i].x,a[i].y);
	shuffle(a+1,a+n+1,rnd);
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++)id[i][j]=j;
		sort(id[i]+1,id[i]+n+1,[&](int x,int y){return a[x]-a[i]<a[y]-a[i];});
	}
	vpii().swap(eg);
	for(int i=1;i<=n;i++)for(int j=1;j<=n;j++)if(i!=j)eg.pb(i,j);
	sort(eg.begin(),eg.end(),[&](pii x,pii y){return a[x.se]-a[x.fi]<a[y.se]-a[y.fi];});
	for(int i=1;i<=n;i++)for(int j=1;j<=n;j++)val[i][j]=dis[i][j]=sqrtl(dot(a[i]-a[j],a[i]-a[j]));
	for(int i=1;i<=n;i++)for(int j=1;j<=n;j++)if(i!=j){
		for(int k=1;k<=n;k++){
			if(Cross(a[k]-a[i],a[j]-a[i])>0 && dot(a[k]-a[i],a[j]-a[i])>=0 && dot(a[k]-a[j],a[i]-a[j])>0)
				val[i][j]+=min(dis[i][k],dis[j][k]);
			if(Z(a[k]-a[i])<a[j]-a[i])
				val[i][j]+=dis[i][k];
			if(Z(a[k]-a[j])<a[j]-a[i])
				val[i][j]-=dis[j][k];
		}
	}
	ld l=0;
	for(int o=1;o<=n;o++){
		init(o);
		if(check(o,l+eps)){
			ld r=inf,mid;
			for(int i=1;i<=50;i++){
				mid=(l+r)/2;
				if(check(o,mid))l=mid;
				else r=mid;
			}
			l=(l+r)/2;
		}
	}
	printf("%.10lf\n",l);
}
signed main(){
	#ifdef do_while_true
		// assert(freopen("data.in","r",stdin));
//		assert(freopen("data.out","w",stdout));
	#endif
	int T;read(T);
	while(T--)solve();
    #ifdef do_while_true
//		cerr<<'\n'<<"Time:"<<1.0*clock()/CLOCKS_PER_SEC*1000<<" ms"<<'\n';
	#endif
	return 0;
}