#include<bits/stdc++.h>
#define ios ios::sync_with_stdio(0), cin.tie(0)
#define time chrono::system_clock::now().time_since_epoch().count()
using namespace std;
#define int long long
using ll = long long;
using pll = pair<int, int>;

const int mod = 998244353, N = 2e5 + 10;

int qmi(int a, int b) {
    int res = 1;
    while (b) {
        if (b & 1) res = res * a % mod;
        a = a * a % mod;
        b >>= 1;
    }
    return res;
}

void solve(){
    int n; cin >> n;
    vector edg(n + 10, vector<int>());
    for (int i = 1; i < n; i ++) {
        int u, v; cin >> u >> v;
        edg[u].push_back(v);
        edg[v].push_back(u);
    }

    vector<int> sz(n + 10, 0);
    vector<int> sum(n + 10, 0), tot(n + 10, 0);
    int res = 0;
    function<void(int, int)> dfs1 = [&] (int u, int p) {
        sz[u] = 1;
        for (auto v : edg[u]) {
            if (v == p) continue;
            dfs1(v, u);
            sz[u] += sz[v];
            sum[u] = (sum[u] + sz[v] * sz[v] % mod) % mod;
            tot[u] = (tot[u] + sum[v]) % mod;
        }
        sum[u] = (sum[u] + sz[u] * sz[u] % mod) % mod;
    };
    function<void(int, int)> dfs2 = [&] (int u, int p) {
        for (auto v : edg[u]) {
            if (p == v) continue;
            res += sz[v] * sz[v] % mod * (n - sz[v]) % mod * (n - sz[v]) % mod;
            res = (res % mod + mod) % mod;
            res += 2 * (n - sz[v]) % mod * (n - sz[v]) % mod * ((sum[v] - sz[v] * sz[v] % mod + mod) % mod) % mod;
            res = (res % mod + mod) % mod;
            res += sum[v] * ((tot[u] - sum[v]) % mod) % mod;
            res = (res % mod + mod) % mod;
            dfs2(v, u);
        }
    };
    dfs1(1, 0);
    dfs2(1, 0);
    int t = n * n % mod * (n - 1) % mod * (n - 1) % mod * qmi(4, mod - 2) % mod;
    res = res * qmi(t, mod - 2) % mod;
    res = (res % mod + mod) % mod;
    cout << res << '\n';
}

signed main()
{
    ios;
    int t = 1;
    cin >> t;
    while (t--)
        solve();
    return 0;
}