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

int main()
{
    int n;
    cin >> n;
    vector<set<int>> v(n + 1);
    for (int i = 1; i <= n; i++)
    {
        int k;
        cin >> k;
        while (k--)
        {
            int x;
            cin >> x;
            v[i].insert(x);
        }
    }
    int m;
    cin >> m;
    while (m--)
    {
        int a, b;
        cin >> a >> b;
        int nc = 0, nt;
        for (auto c : v[a]) if (v[b].count(c)) nc++;
        nt = v[a].size() + v[b].size() - nc; 
        printf("%.2lf%%\n", nc * 1.0 / nt * 100);
    }

    return 0;
}