#include<cstdio>

#include<queue>

#include<cctype>

#include<cstring>

#include<stack>

#include<cmath>

#include<algorithm>

using namespace std;

typedef double dl;

const dl eps=1e-;

const int N=;

struct Point{

    dl x;

    dl y;

}p[N],point[N],q[N],z;

//point，初始点

//q，暂时存可行点

//p，记录可行点

int n,curcnt,cnt;

//curcnt，暂时存可行点个数

//cnt，记录可行点个数

inline Point getmag(Point a,Point b){

    Point s;

    s.x=b.x-a.x;s.y=b.y-a.y;

    return s;

}

inline dl multiX(Point a,Point b){

    return a.x*b.y-b.x*a.y;

}

inline void getline(Point x,Point y,dl &a,dl &b,dl &c){

    a=y.y-x.y;

    b=x.x-y.x;

    c=y.x*x.y-x.x*y.y;

    return;

}

inline Point intersect(Point x,Point y,dl a,dl b,dl c){

    Point s;

    dl u=fabs(a*x.x+b*x.y+c);

    dl v=fabs(a*y.x+b*y.y+c);

    s.x=(x.x*v+y.x*u)/(u+v);

    s.y=(x.y*v+y.y*u)/(u+v);

    return s;

}

inline void cut(dl a,dl b,dl c){

    curcnt=;

    for(int i=;i<=cnt;i++){

        if(a*p[i].x+b*p[i].y+c>-eps)q[++curcnt]=p[i];

        else{

            if(a*p[i-].x+b*p[i-].y+c>eps){

                q[++curcnt]=intersect(p[i],p[i-],a,b,c);

              }

            if(a*p[i+].x+b*p[i+].y+c>eps){

                q[++curcnt]=intersect(p[i],p[i+],a,b,c);

               }

        }

    }

    for(int i=;i<=curcnt;i++)p[i]=q[i];

    p[curcnt+]=p[];p[]=p[curcnt];

    cnt=curcnt;

    return;

}

inline void init(){

    for(int i=;i<=n;i++)p[i]=point[i];

    z.x=z.y=;

    p[n+]=p[];

    p[]=p[n];

    point[n+]=point[];

    cnt=n;

    return;

}

inline void regular(){//调换方向

    for(int i=;i<(n+)/;i++)swap(point[i],point[n-i]);

    return;

}

inline bool solve(){

    //注意：默认点是顺时针，如果题目不是顺时针，规整化方向

    init();

    for(int i=;i<=n;i++){

        dl a,b,c;

        getline(point[i],point[i+],a,b,c);

        cut(a,b,c);

    }

    return cnt;

}

int main(){

    int t;

    scanf("%d",&t);

    while(t--){

        scanf("%d",&n);

        for(int i=;i<=n;i++){

            scanf("%lf%lf",&point[i].x,&point[i].y);

        }

        if(!solve())puts("NO");

        else puts("YES");

    }

    return ;

}