// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#else
#define debug(x...) {};
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define double long double
#define int long long
#define P 1000000007
#define MAXN 200010

int binary_search(vector<int> &a, int l, int r, int x) {
    int ans = -1;
    while (l <= r) {
        int mid = l + (r-l) / 2;
        if (a[mid] <= x) l = mid + 1;
        else ans = mid, r = mid - 1;
    }
    return ans;
}

void solve() {
    int n; cin >> n;
    vector<int> a(n), b(n);
    rep(i, 0, n) cin >> a[i];
    rep(i, 0, n) cin >> b[i];
    sort(a.begin(), a.end());
    sort(b.begin(), b.end());
    vector<int> c;
    for (int i = n-1; i >= 0; --i) {
        int id = binary_search(a, 0, n-1, b[i]);
        if (!~id) {
            cout << 0 << endl;
            return;
        }
        c.push_back(n - id);
    }
    int ans = 1;
    rep(i, 0, sz(c)) {
        if (c[i] - i <= 0) {
            cout << 0 << endl;
            return;
        }
        ans = ans * (c[i] - i) % P;
    }
    cout << ans << endl;
}

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

    int _; cin >> _;
    while (_--) solve();

    return 0;
}