#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 1000000000000000001


int main(){
	vector<mint> kei = {-2,2,-8,2,-2,1,1,1,1,1,1,1,1};

vector<vector<int>> bunsi = {{2,0,2,0},{0,2,2,0},{1,1,1,1},{2,0,0,2},{0,2,0,2},{2,0,2,0},{0,2,2,0},{2,0,0,2},{0,2,0,2},{2,0,2,0},{2,0,0,2},{0,2,2,0},{0,2,0,2}};
	//cout<<kei.size()<<' '<<bunsi.size()<<endl;
	int _t;
	cin>>_t;
	
	rep(_,_t){
		int n;
		cin>>n;
		vector<mint> x(n),y(n);
		rep(i,n){
			int a,b;
			cin>>a>>b;
			x[i] = a,y[i] = b;
		}
		mint ans = 0;
		rep(k,kei.size()){
			mint sum = 0;
			rep(i,n){
				mint A = x[i] * x[i] + y[i] * y[i];
				{
					mint t = 1;
					t *= x[i].pow(bunsi[k][2]);
					t *= y[i].pow(bunsi[k][3]);
					if(k<5)t /= A;
					else if(k>=9)t /= A*A;
					ans += t * sum * kei[k];
				}
				{
					mint t = 1;
					t *= x[i].pow(bunsi[k][0]);
					t *= y[i].pow(bunsi[k][1]);
					if(k<5)t /= A;
					else if(k<9)t /= A*A;
					sum += t;
				}
				/*
				for(int j=i+1;j<n;j++){
					mint t = 1;
					
					
					
					mint B = x[j] * x[j] + y[j] * y[j];
					if(k<5){
						t /= A*B;
						
					}
					else if(k<9){
						t /= A*A;
						
					}
					else t /= B*B;
					t *= kei[k];
					ans += t;
				}
				*/
			}
		}
		cout<<ans.val()<<endl;
	}
	
	return 0;
}