#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N = 1e6+5;
const int mod = 998244353;
vector<int>g[N];

int qpow(int a, int b){
	a %= mod;
	int ans = 1;
	while(b){
		if(b&1)ans= ans * a%mod;
		b>>=1;
		a = a*a%mod;
	}
	return ans;
}
int tot = 0;
int siz[N], fs[N];
int n;
void dfs1(int u, int fa){
	siz[u] = 1;
	for(auto v: g[u]) if(v != fa){
		dfs1(v, u);
		siz[u] = (siz[u] + siz[v])%mod;
		fs[u] = (fs[u] + siz[v]*siz[v]%mod)%mod;
	}
	fs[u] = (fs[u] + siz[u]*siz[u]%mod)%mod;
	int x = siz[u] * (n - siz[u]);
	tot = (tot + x*x%mod)%mod;
}

int tot2 = 0;
void dfs2(int u, int fa){
	
	int fk = 0;
	int ans = 0;
	for(auto v: g[u])if(v!=fa){
		dfs2(v, u);
		//case1
		int x = (n-siz[v])*(n-siz[v])%mod;
		int y = (fs[v] - siz[v]*siz[v]%mod)%mod;
		x = (x + mod)%mod;
		y = (y + mod)%mod;
		ans = (ans + 2*x%mod*y%mod)%mod;
		//case2
		ans = (ans + 2*fk%mod*fs[v]%mod)%mod;
		fk = (fk + fs[v])%mod;
	}
	// tot2 += ans;
	tot2 = (tot2 + ans)%mod;
	// cout << u << ' ' << ans << endl;
}

void solve()
{	
	cin >> n;
	tot = tot2 = 0;
	for(int i=1; i<=n; i++){
		g[i].clear();
		siz[i] = fs[i] = 0;
	}
	for(int i=1; i<n; i++){
		int u, v; cin >> u >> v;
		g[u].push_back(v);
		g[v].push_back(u);
	}	
	dfs1(1, 0);
	dfs2(1, 0);
	// cout << tot << ' ' << tot2 << endl;
	tot = (tot + tot2)%mod;
	int base = n*(n-1)/2;
	base = base*base%mod;
	tot = (tot + mod)%mod;
	cout << tot*qpow(base, mod-2)%mod << endl;
// 	
}  
signed main (){
	std::ios::sync_with_stdio(false);  
	cin.tie(NULL); 
	cout.tie(NULL);
	int t;
	cin>>t;
	while(t--)
		solve();
}