#include<bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define SZ(x) ((int)x.size())
#define L(i,u) for (register int i=head[u]; i; i=nxt[i])
#define rep(i,a,b) for (register int i=(a); i<=(b); i++)
#define per(i,a,b) for (register int i=(a); i>=(b); i--)
using namespace std;
typedef long long ll;
typedef unsigned int ui;
typedef pair<int,int> Pii;
typedef pair<double,int> Pdi;
typedef vector<int> Vi;
template<class T> inline void read(T &x){
    x=0; char c=getchar(); int f=1;
    while (!isdigit(c)) {if (c=='-') f=-1; c=getchar();}
    while (isdigit(c)) {x=x*10+c-'0'; c=getchar();} x*=f;
}
template<class T> inline void umin(T &x, T y){x=x<y?x:y;}
template<class T> inline void umax(T &x, T y){x=x>y?x:y;}
inline ui R() {
    static ui seed=416;
    return seed^=seed>>5,seed^=seed<<17,seed^=seed>>13;
}
const int N = 1003;
struct rec{
    int x1,y1,x2,y2;
}a[N],f;
int n,m,s[N],t[N],heng[N][N],shu[N][N];double dis[N][N];
void ini(rec c){
    s[++n]=c.x1;
    s[++n]=c.x2;
    t[++m]=c.y1;
    t[++m]=c.y2;
}
priority_queue<Pdi,vector<Pdi>,greater<Pdi> >heap;
inline double calc(int i, int j, int x, int y){
    if(i+j>x+y)swap(i,x),swap(j,y);
    if(i==x)return (t[y]-t[y-1])/(1.0+heng[i][j]);
    return (s[x]-s[x-1])/(1.0+shu[i][j]);
}
rec getreal(rec c){
    c.x1=lower_bound(s+1,s+n+1,c.x1)-s;
    c.x2=lower_bound(s+1,s+n+1,c.x2)-s;
    c.y1=lower_bound(t+1,t+m+1,c.y1)-t;
    c.y2=lower_bound(t+1,t+m+1,c.y2)-t;
    return c;
}
int dx[]={1,-1,0,0};
int dy[]={0,0,1,-1};
int main() {
    int T;read(T);while(T--){
        int tot;read(tot);
        rep(i,1,tot)read(a[i].x1),read(a[i].y1),read(a[i].x2),read(a[i].y2);
        read(f.x1),read(f.y1),read(f.x2),read(f.y2);
        n=m=0;rep(i,1,tot)ini(a[i]);ini(f);
        sort(s+1,s+n+1);sort(t+1,t+m+1);assert(n==m);//no!!!
        memset(heng,0,sizeof(heng));memset(shu,0,sizeof(shu));f=getreal(f);
        rep(i,1,tot){
            a[i]=getreal(a[i]);
            a[i].y2--;
            heng[a[i].x1][a[i].y1]++;
            heng[a[i].x1][a[i].y2+1]--;
            heng[a[i].x2+1][a[i].y1]--;
            heng[a[i].x2+1][a[i].y2+1]++;
            a[i].y2++;
            a[i].x2--;
            shu[a[i].x1][a[i].y1]++;
            shu[a[i].x1][a[i].y2+1]--;
            shu[a[i].x2+1][a[i].y1]--;
            shu[a[i].x2+1][a[i].y2+1]++;
            a[i].x2++;
        }
        rep(i,1,n)rep(j,1,m)heng[i][j]+=heng[i][j-1];
        rep(i,1,n)rep(j,1,m)heng[i][j]+=heng[i-1][j];
        rep(i,1,n)rep(j,1,m)shu[i][j]+=shu[i][j-1];
        rep(i,1,n)rep(j,1,m)shu[i][j]+=shu[i-1][j];
        rep(i,1,n)rep(j,1,m)dis[i][j]=1e9+3;dis[f.x1][f.y1]=0;
        heap.push(Pdi(0,f.x1*N+f.y1));
        while(!heap.empty()){
            Pdi tmp=heap.top();heap.pop();int x=tmp.se/N,y=tmp.se%N;
            if(dis[x][y]!=tmp.fi)continue;
            rep(k,0,3)if(x+dx[k]>=1&&x+dx[k]<=n&&y+dy[k]>=1&&y+dy[k]<=m)
                if(dis[x+dx[k]][y+dy[k]]>dis[x][y]+calc(x,y,x+dx[k],y+dy[k])){
                    dis[x+dx[k]][y+dy[k]]=dis[x][y]+calc(x,y,x+dx[k],y+dy[k]);
                    heap.push(Pdi(dis[x+dx[k]][y+dy[k]],(x+dx[k])*N+y+dy[k]));
                }
        }
        printf("%.5lf\n",dis[f.x2][f.y2]);
    }
    return 0;
}