#include<bits/stdc++.h>
using namespace std;
using ll=long long;
template<typename T>
ostream& operator << (ostream &out,const vector<T>&x){
	if(x.empty())return out<<"[]";
	out<<'['<<x[0];
	for(int len=x.size(),i=1;i<len;i++)out<<','<<x[i];
	return out<<']';
}
template<typename T>
vector<T> ary(const T *a,int l,int r){
	return vector<T>{a+l,a+1+r};
}
template<typename T>
void debug(T x){
	cerr<<x<<'\n';
}
template<typename T,typename ...S>
void debug(T x,S ...y){
	cerr<<x<<' ',debug(y...);
}
const int N=5e2+10,M=N*N;
int T,n,m,p[N];
struct vec{
	int x,y;
	vec(int a=0,int b=0):x(a),y(b){}
}a[N];
ll dot(const vec &a,const vec &b){
	return 1ll*a.x*b.x+1ll*a.y*b.y;
}
ll cross(const vec &a,const vec &b){
	return 1ll*a.x*b.y-1ll*a.y*b.x;
}
ll dis2(const vec &a){
	return dot(a,a);
}
vec operator - (const vec &a,const vec &b){
	return vec(a.x-b.x,a.y-b.y);
}
int find(const vec &a){
	if(!a.y)return a.x>0?0:2;
	else return a.y>0?1:3;
}
bool operator < (const vec &a,const vec &b){
	int x=find(a),y=find(b);
	return x^y?x<y:cross(a,b)>0;
}
struct zj{
	vec ang;
	int u,v;
	ll x,y;
	bool operator < (const zj &a)const{
		return ang<a.ang;
	}
}b[M];
double f[N];
bool chk(int s,double k){
	fill(f+1,f+1+n,-INFINITY),f[s]=0;
	for(int i=1;i<=m;i++){
		f[b[i].v]=max(f[b[i].v],f[b[i].u]+b[i].x-k*b[i].y);
	}
	return f[s]>0;
}
mt19937 rnd(time(0));
const double eps=1e-10;
void get(){
	cin>>n,m=0;
	for(int i=1;i<=n;i++)cin>>a[i].x>>a[i].y;
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			if(i==j)continue;
			b[++m]={a[j]-a[i],i,j,cross(a[i],a[j]),dis2(a[i]-a[j])};
		}
	}
	sort(b+1,b+1+m);
	iota(p,p+1+n,0),shuffle(p+1,p+1+n,rnd);
	double ans=0;
	for(int x=1,i;i=p[x],x<=n;x++){
		if(!chk(i,ans))continue;
		double l=ans,r=1e8,mid;
		for(;(r-l)/max(1.0,l)>eps;){
			mid=(l+r)/2;
			if(chk(i,mid))l=mid;
			else r=mid;
		}
		ans=l;
	}
	printf("%.16lf\n",ans/2);
}
int main(){
	for(cin>>T;T--;)get();
	return 0;
}