/*
* @Author: NanoApe
* @Date:   2019-08-17 17:59:32
* @Last Modified by:   NanoApe
* @Last Modified time: 2019-08-17 19:30:02
*/

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <cmath>
#include <algorithm>
#include <iostream>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <vector>

using namespace std;

#define rep(i, l, r) for(int i=l; i<=r; i++)
#define dow(i, l, r) for(int i=l; i>=r; i--)
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define clr(x, c) memset(x,c,sizeof(x))

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> Pii;

inline int read()
{
    int x=0,f=0; char ch=getchar();
    while (ch<'0' || '9'<ch) f|=ch=='-', ch=getchar();
    while ('0'<=ch && ch<='9') x=x*10+ch-'0', ch=getchar();
    return f?-x:x;
}

#define maxn 209
#define maxS 409

int x1[maxn], y1[maxn], x2[maxn], y2[maxn];
vector<int> v;
map<int,int> mx, my;
int numx[maxS], numy[maxS];
double d[maxS][maxS];
int C[maxS][maxS], U[maxS][maxS], D[maxS][maxS], R[maxS][maxS], L[maxS][maxS];
bool tag[maxS][maxS];
queue<Pii> q;

int main()
{
    int T = read();
    while (T--) {
        int n = read();
        rep(i, 1, n) x1[i] = read(), y1[i]=read(), x2[i]=read(), y2[i]=read();
        int xa = read(), ya = read(), xb = read(), yb = read();

        int xRange = 0;
        v.clear();
        mx.clear();
        rep(i, 1, n) v.push_back(x1[i]), v.push_back(x2[i]);
        v.push_back(xa); v.push_back(xb);
        sort(v.begin(), v.end());
        rep(i, 0, (int)(v.size())-1) {
            if (i == 0 || v[i] != v[i-1])
                xRange++;
            numx[xRange] = v[i];
            mx[v[i]] = xRange;
        }

        int yRange = 0;
        v.clear();
        my.clear();
        rep(i, 1, n) v.push_back(y1[i]), v.push_back(y2[i]);
        v.push_back(ya); v.push_back(yb);
        sort(v.begin(), v.end());
        rep(i, 0, (int)(v.size())-1) {
            if (i == 0 || v[i] != v[i-1])
                yRange++;
            numy[yRange] = v[i];
            my[v[i]] = yRange;
        }

        clr(U,0); clr(D,0); clr(L,0); clr(R,0); clr(C,0);
        rep(o, 1, n) {
            x1[o] = mx[x1[o]];
            y1[o] = my[y1[o]];
            x2[o] = mx[x2[o]];
            y2[o] = my[y2[o]];

            rep(i, x1[o]+1, x2[o]-1) rep(j, y1[o]+1, y2[o]-1) C[i][j]++;
            rep(j, y1[o], y2[o]-1) U[x1[o]][j]++, U[x2[o]][j]++; rep(i, x1[o]+1, x2[o]-1) U[i][y1[o]]++;
            rep(j, y1[o]+1, y2[o]) D[x1[o]][j]++, D[x2[o]][j]++; rep(i, x1[o]+1, x2[o]-1) D[i][y2[o]]++;
            rep(i, x1[o]+1, x2[o]) L[i][y1[o]]++, L[i][y2[o]]++; rep(j, y1[o]+1, y2[o]-1) L[x2[o]][j]++;
            rep(i, x1[o], x2[o]-1) R[i][y1[o]]++, R[i][y2[o]]++; rep(j, y1[o]+1, y2[o]-1) R[x1[o]][j]++;
        }
        xa = mx[xa];
        ya = my[ya];
        xb = mx[xb];
        yb = my[yb];

        rep(i, 1, xRange) rep(j, 1, yRange) d[i][j] = 1e100, tag[i][j] = false;
        d[xa][ya] = 0, tag[xa][ya] = true;
        q.push(make_pair(xa, ya));
        while (!q.empty()) {
            Pii a = q.front(); q.pop();
            int x = a.fi, y = a.se;
            tag[x][y] = false;
            if (y+1 <= yRange && d[x][y+1] > d[x][y]+1.*(numy[y+1]-numy[y])/(C[x][y]+U[x][y]+1)) { d[x][y+1] = d[x][y]+1.*(numy[y+1]-numy[y])/(C[x][y]+U[x][y]+1); if (!tag[x][y+1]) {q.push(make_pair(x, y+1)), tag[x][y+1] = 1;}}
            if (y-1 >= 1 && d[x][y-1] > d[x][y]+1.*(numy[y]-numy[y-1])/(C[x][y]+D[x][y]+1)) { d[x][y-1] = d[x][y]+1.*(numy[y]-numy[y-1])/(C[x][y]+D[x][y]+1); if (!tag[x][y-1]) {q.push(make_pair(x, y-1)), tag[x][y-1] = 1;}}
            if (x-1 >= 1 && d[x-1][y] > d[x][y]+1.*(numx[x]-numx[x-1])/(C[x][y]+L[x][y]+1)) { d[x-1][y] = d[x][y]+1.*(numx[x]-numx[x-1])/(C[x][y]+L[x][y]+1); if (!tag[x-1][y]) {q.push(make_pair(x-1, y)), tag[x-1][y] = 1;}}
            if (x+1 <= xRange && d[x+1][y] > d[x][y]+1.*(numx[x+1]-numx[x])/(C[x][y]+R[x][y]+1)) { d[x+1][y] = d[x][y]+1.*(numx[x+1]-numx[x])/(C[x][y]+R[x][y]+1); if (!tag[x+1][y]) {q.push(make_pair(x+1, y)), tag[x+1][y] = 1;}}
        }
        printf("%.5lf\n", d[xb][yb]);
    }
}