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

const double inf = 1e15;

int T, n, xl[205], xr[205], yl[205], yr[205], sumx[405][405], sumy[405][405], xa, xb, ya, yb;
bool done[405][405];
double dis[405][405];

int main()
{
    scanf("%d", &T);
    while (T--)
    {
        vector<int> vx, vy;
        scanf("%d", &n);
        for (int i = 0; i < n; ++i)
        {
            scanf("%d%d%d%d", xl + i, yl + i, xr + i, yr + i);
            vx.push_back(xl[i]), vx.push_back(xr[i]);
            vy.push_back(yl[i]), vy.push_back(yr[i]);
        }
        scanf("%d%d%d%d", &xa, &ya, &xb, &yb);
        vx.push_back(xa), vx.push_back(xb);
        vy.push_back(ya), vy.push_back(yb);
        sort(vx.begin(), vx.end());
        vx.erase(unique(vx.begin(), vx.end()), vx.end());
        sort(vy.begin(), vy.end());
        vy.erase(unique(vy.begin(), vy.end()), vy.end());
        for (int i = 0; i < (int)vx.size(); ++i)
            for (int j = 0; j < (int)vy.size(); ++j)
                dis[i][j] = inf, done[i][j] = false, sumx[i][j] = sumy[i][j] = 0;
        xa = lower_bound(vx.begin(), vx.end(), xa) - vx.begin();
        xb = lower_bound(vx.begin(), vx.end(), xb) - vx.begin();
        ya = lower_bound(vy.begin(), vy.end(), ya) - vy.begin();
        yb = lower_bound(vy.begin(), vy.end(), yb) - vy.begin();
        for (int i = 0; i < n; ++i)
        {
            xl[i] = lower_bound(vx.begin(), vx.end(), xl[i]) - vx.begin();
            xr[i] = lower_bound(vx.begin(), vx.end(), xr[i]) - vx.begin();
            yl[i] = lower_bound(vy.begin(), vy.end(), yl[i]) - vy.begin();
            yr[i] = lower_bound(vy.begin(), vy.end(), yr[i]) - vy.begin();
            if (xl[i] < xr[i])
            {
                ++sumx[xl[i]][yl[i]];
                --sumx[xr[i]][yl[i]];
                if (yr[i] + 1 < (int)vy.size())
                {
                    --sumx[xl[i]][yr[i] + 1];
                    ++sumx[xr[i]][yr[i] + 1];
                }
            }
            if (yl[i] < yr[i])
            {
                ++sumy[xl[i]][yl[i]];
                --sumy[xl[i]][yr[i]];
                if (xr[i] + 1 < (int)vx.size())
                {
                    --sumy[xr[i] + 1][yl[i]];
                    ++sumy[xr[i] + 1][yr[i]];
                }
            }
        }
        for (int i = 0; i < (int)vx.size(); ++i)
            for (int j = 1; j < (int)vy.size(); ++j)
                sumx[i][j] += sumx[i][j - 1], sumy[i][j] += sumy[i][j - 1];
        for (int i = 1; i < (int)vx.size(); ++i)
            for (int j = 0; j < (int)vy.size(); ++j)
                sumx[i][j] += sumx[i - 1][j], sumy[i][j] += sumy[i - 1][j];
        priority_queue<pair<double, pair<int, int>>> q;
        q.emplace(dis[xa][ya] = 0, make_pair(xa, ya));
        while (!q.empty())
        {
            auto p = q.top(); q.pop();
            int x = p.second.first, y = p.second.second;
            if (done[x][y]) continue;
            done[x][y] = true;
            if (x > 0)
            {
                double w = 1.0 * (vx[x] - vx[x - 1]) / (1 + sumx[x - 1][y]);
                if (dis[x][y] + w < dis[x - 1][y])
                    q.emplace(-(dis[x - 1][y] = dis[x][y] + w), make_pair(x - 1, y));
            }
            if (x + 1 < (int)vx.size())
            {
                double w = 1.0 * (vx[x + 1] - vx[x]) / (1 + sumx[x][y]);
                if (dis[x][y] + w < dis[x + 1][y])
                    q.emplace(-(dis[x + 1][y] = dis[x][y] + w), make_pair(x + 1, y));
            }
            if (y > 0)
            {
                double w = 1.0 * (vy[y] - vy[y - 1]) / (1 + sumy[x][y - 1]);
                if (dis[x][y] + w < dis[x][y - 1])
                    q.emplace(-(dis[x][y - 1] = dis[x][y] + w), make_pair(x, y - 1));
            }
            if (y + 1 < (int)vy.size())
            {
                double w = 1.0 * (vy[y + 1] - vy[y]) / (1 + sumy[x][y]);
                if (dis[x][y] + w < dis[x][y + 1])
                    q.emplace(-(dis[x][y + 1] = dis[x][y] + w), make_pair(x, y + 1));
            }
        }
        printf("%.5f\n", dis[xb][yb]);
    }
    return 0;
}