#include<bits/stdc++.h>
using namespace std;

#define reg register
typedef long long ll;
#define rep(i,a,b) for(int i=a,i##end=b;i<=i##end;++i)
#define drep(i,a,b) for(int i=a,i##end=b;i>=i##end;--i)

char IO;
int rd(){
    int s=0,f=0;
    while(!isdigit(IO=getchar())) if(IO=='-') f=1;
    do s=(s<<1)+(s<<3)+(IO^'0');
    while(isdigit(IO=getchar()));
    return f?-s:s;
}

const int N=810;
const int z[5][4]={{0,1},{0,-1},{1,0},{-1,0}};

int n;
int hx[N],cx;
int hy[N],cy;
int x1[N],yy[N],x2[N],y2[N];
int sx,sy,fx,fy;
int cnt[N][N][4];
double dp[N][N];

struct node{
    int x,y;
    double dis;
    bool operator < (const node __) const{
        return dis>__.dis;
    }
};
priority_queue <node> Q;





int main(){
    rep(kase,1,rd()){
        n=rd();cx=cy=0;
        rep(i,1,n) {
            x1[i]=rd(),yy[i]=rd(),x2[i]=rd(),y2[i]=rd();
            hx[++cx]=x1[i];
            hx[++cx]=x2[i];
            hy[++cy]=yy[i];
            hy[++cy]=y2[i];
        }
        sx=rd(),sy=rd(),fx=rd(),fy=rd();
        hx[++cx]=sx;
        hx[++cx]=fx;
        hy[++cy]=sy;
        hy[++cy]=fy;
        sort(hx+1,hx+cx+1),cx=unique(hx+1,hx+cx+1)-hx-1;
        sort(hy+1,hy+cy+1),cy=unique(hy+1,hy+cy+1)-hy-1;
        memset(cnt,0,sizeof cnt);

        rep(i,1,n) {
            x1[i]=lower_bound(hx+1,hx+cx+1,x1[i])-hx;
            x2[i]=lower_bound(hx+1,hx+cx+1,x2[i])-hx;
            yy[i]=lower_bound(hy+1,hy+cy+1,yy[i])-hy;
            y2[i]=lower_bound(hy+1,hy+cy+1,y2[i])-hy;
            rep(x,x1[i]+1,x2[i]-1) rep(y,yy[i]+1,y2[i]-1) rep(o,0,3) cnt[x][y][o]++;
            rep(x,x1[i],x1[i]) rep(y,yy[i]+1,y2[i]-1) cnt[x][y][0]++,cnt[x][y][1]++,cnt[x][y][2]++;
            rep(x,x2[i],x2[i]) rep(y,yy[i]+1,y2[i]-1) cnt[x][y][0]++,cnt[x][y][1]++,cnt[x][y][3]++;
            rep(y,yy[i],yy[i]) rep(x,x1[i]+1,x2[i]-1) cnt[x][y][2]++,cnt[x][y][3]++,cnt[x][y][0]++;
            rep(y,y2[i],y2[i]) rep(x,x1[i]+1,x2[i]-1) cnt[x][y][2]++,cnt[x][y][3]++,cnt[x][y][1]++;
            cnt[x1[i]][yy[i]][0]++;
            cnt[x1[i]][yy[i]][2]++;
            cnt[x2[i]][yy[i]][0]++;
            cnt[x2[i]][yy[i]][3]++;
            ;
            cnt[x1[i]][y2[i]][1]++;
            cnt[x1[i]][y2[i]][2]++;
            cnt[x2[i]][y2[i]][1]++;
            cnt[x2[i]][y2[i]][3]++;
            ;
        }

        fx=lower_bound(hx+1,hx+cx+1,fx)-hx;
        sx=lower_bound(hx+1,hx+cx+1,sx)-hx;
        sy=lower_bound(hy+1,hy+cy+1,sy)-hy;
        fy=lower_bound(hy+1,hy+cy+1,fy)-hy;
        rep(i,1,cx) rep(j,1,cy) dp[i][j]=1e12;
        Q.push((node){sx,sy,0});dp[sx][sy]=0;
        while(!Q.empty()) {
            int x=Q.top().x,y=Q.top().y;
            double t=Q.top().dis;
            Q.pop();
            if(t>dp[x][y]) continue;
            //cout<<x<<' '<<y<<' '<<t<<endl;
            rep(i,0,3) {
                int x1=x+z[i][0],y1=y+z[i][1];
                if(x1<1||y1<1||x1>cx||y1>cy) continue;
                double w=1.0*(abs(hx[x1]-hx[x])+abs(hy[y1]-hy[y]))/(1.0*cnt[x][y][i]+1.0);
                //cout<<"#"<<x1<<' '<<y1<<' '<<w<<' '<<endl;
                if(dp[x1][y1]>dp[x][y]+w) {
                    dp[x1][y1]=dp[x][y]+w;
                    Q.push((node){x1,y1,dp[x1][y1]});
                }
            }
        }
        //cout<<sx<<' '<<sy<<' '<<fx<<' '<<fy<<endl;
        printf("%.5lf\n",dp[fx][fy]);
    }
}