/*

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       _/_/        _/_/_/      _/_/_/        _/_/_/      _/  _/_/               _/_/_/
    _/    _/    _/            _/    _/    _/    _/      _/_/          _/       _/    _/
   _/    _/    _/            _/    _/    _/    _/      _/            _/       _/    _/
    _/_/        _/_/_/      _/    _/      _/_/_/      _/            _/       _/    _/

*/
#include<bits/stdc++.h>
#define int long long

using namespace std;
const int mod=998244353;

int qpow(int a,int b){
    int ans=1;
    for(;b;b>>=1){
        if(b&1) ans=ans*a%mod;
        a=a*a%mod;
    }
    return ans;
}

void solve(){
    int n;
    cin>>n;
    vector<vector<int>>e(n+1);
    for(int i=1;i<n;++i){
        int u,v;
        cin>>u>>v;
        e[u].push_back(v);
        e[v].push_back(u);
    }
    vector<int>s(n+1,0ll),sz(n+1);
    int res=0;
    auto dfs=[&](auto dfs,int u,int fa)->void{
        sz[u]=1;v
        int ans=0,sum=0;
        for(auto v:e[u]){
            if(v==fa) continue;
            dfs(dfs,v,u);
            res+=(n-sz[v])*(n-sz[v])%mod*sz[v]%mod*sz[v]%mod;
            if(res>=mod) res-=mod;

            int tmp=s[v]-sz[v]*sz[v]%mod+mod;
            if(tmp>=mod) tmp-=mod;

            res+=(n-sz[v])*(n-sz[v])%mod*tmp%mod*2%mod;
            if(res>=mod) res-=mod;

            ans+=sum*s[v]%mod;
            if(ans>=mod) ans-=mod;

            sum+=s[v];
            if(sum>=mod) sum-=mod;

            sz[u]+=sz[v];

            s[u]+=s[v];
            if(s[u]>=mod) s[u]-=mod;
        }

        s[u]+=sz[u]*sz[u]%mod;
        if(s[u]>=mod) s[u]-=mod;

        res+=2*ans%mod;
        if(res>=mod) res-=mod;
    };
    dfs(dfs,1,0);
    int inv=n*(n-1)/2%mod;
    inv=inv*inv%mod;
    cout<<res*qpow(inv,mod-2)%mod<<"\n";
}


signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    int t=1;
    cin>>t;
    while(t--) solve();
}

answer.code: In lambda function:
answer.code:38:17: error: ‘v’ was not declared in this scope
   38 |         sz[u]=1;v
      |                 ^
answer.code:52:13: error: ‘ans’ was not declared in this scope; did you mean ‘abs’?
   52 |             ans+=sum*s[v]%mod;
      |             ^~~
      |             abs
answer.code:52:18: error: ‘sum’ was not declared in this scope
   52 |             ans+=sum*s[v]%mod;
      |                  ^~~
answer.code:67:16: error: ‘ans’ was not declared in this scope; did you mean ‘abs’?
   67 |         res+=2*ans%mod;
      |                ^~~
      |                abs