#include<bits/stdc++.h>
#define pb push_back
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;

const int N=1e5+5;
const ll MOD=998244353;
int n,tot;
int sz[N],dfn[N],dfr[N];
ll ans;
vector<int> ve[N];

void add(ll&x,ll y) {x=(x+y)%MOD;}

struct segtree
{
    struct node 
    {
        ll ss,s;
        node friend operator + (node a,node b)
        {
            return node{a.ss+b.ss,a.s+b.s};
        }
    }s[N*4];
    ll tag[N*4];

    void build(int n) {for(int i=1;i<=n*4;i++) s[i]={0,0},tag[i]=0;}

    void add(int x,int len,ll val)
    {
        s[x].ss+=s[x].s*val*2+val*val*len;
        s[x].s+=val*len;
        tag[x]+=val;
    }

    void pushdown(int x,int l,int r)
    {
        if(!tag[x]) return;
        int mid=(l+r)>>1;
        add(x<<1,mid-l+1,tag[x]),add(x<<1|1,r-mid,tag[x]),tag[x]=0;
    }

    void modify(int x,int l,int r,int L,int R,int val)
    {
        if(L<=l&&r<=R) {add(x,r-l+1,val); return;}
        pushdown(x,l,r);
        int mid=(l+r)>>1;
        if(L<=mid) modify(x<<1,l,mid,L,R,val);
        if(R>mid) modify(x<<1|1,mid+1,r,L,R,val);
        s[x]=s[x<<1]+s[x<<1|1];
    }
    void modify(int L,int R,int val) {modify(1,1,n,L,R,val);}

    ll query(int x,int l,int r,int L,int R)
    {
        if(L<=l&&r<=R) return s[x].ss;
        pushdown(x,l,r);
        int mid=(l+r)>>1;
        ll res=0;
        if(L<=mid) res+=query(x<<1,l,mid,L,R);
        if(R>mid) res+=query(x<<1|1,mid+1,r,L,R);
        return res;
    }
    ll query(int L,int R) {return query(1,1,n,L,R);}
}TR;

ll ksm(ll a,ll b)
{
    ll res=1;
    for(ll i=b;i;i>>=1,a=a*a%MOD) if(i&1) res=res*a%MOD;
    return res;
}

void input()
{
    scanf("%d",&n);
    tot=0,ans=0;
    for(int i=1;i<=n;i++) sz[i]=0,ve[i].clear();
    for(int i=1,x,y;i<n;i++) scanf("%d%d",&x,&y),ve[x].pb(y),ve[y].pb(x);
    TR.build(n);
}

void dfs1(int x,int fa)
{
    dfn[x]=dfr[x]=++tot,sz[x]=1;
    for(int v:ve[x]) if(v!=fa)
    {
        dfs1(v,x),sz[x]+=sz[v];
        dfr[x]=dfr[v];
    }
    TR.modify(dfn[x],dfn[x],sz[x]);
}

void dfs2(int x,int fa,ll sum)
{
    ll res=(sum+(TR.s[1].ss-TR.query(dfn[x],dfr[x])))%MOD;
    //cerr<<' '<<x<<' '<<sum<<' '<<res<<endl;
    add(ans,res*sz[x]%MOD*sz[x]%MOD);
    if(fa!=0) sum+=(n-sz[x])*(n-sz[x]);
    for(int v:ve[x]) if(v!=fa)
    {
        TR.modify(dfn[x],dfn[x],-sz[v]);
        TR.modify(dfn[v],dfn[v],n-sz[v]);
        dfs2(v,x,sum);
        TR.modify(dfn[v],dfn[v],sz[v]-n);
        TR.modify(dfn[x],dfn[x],sz[v]);
    }
}

void solve()
{
    input();
    dfs1(1,0);
    dfs2(1,0,0);
    //cerr<<' '<<ans<<endl;
    ll cnt=1ll*n*(n-1)/2;
    ll deno=ksm(cnt%MOD,MOD-2);
    printf("%lld\n",ans*deno%MOD*deno%MOD);
}

int main()
{
    int T=1;
    scanf("%d",&T);
    for(int cs=1;cs<=T;cs++) solve();
}