// Problem: D. NEQ
// Contest: undefined - NOIP2024训练赛 06
// URL: http://www.noi.ac/contest/1158/problem/2693
// Memory Limit: 1024 MB
// Time Limit: 1000 ms
// 
// Powered by CP Editor (https://cpeditor.org)

#include<bits/stdc++.h>
#define int long long
#define fi first
#define se second
#define PII pair<int, int>

using namespace std;

const int N = 4e5 + 10, M = 1e6 + 10, mod = 1e9 + 7, INF = 0x3f3f3f3f;

int n, m, q, ans;
int s[N], dp[N];

// vector<int> e[N];

int A(int n, int m) 
{
	int res = 1;
	for(int i = n; i >= n - m + 1; i--) res = (res * i) % mod;
	return res;
}

signed main()
{
	ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
	int T; cin >> T;
	while(T --)
	{
		cin >> n >> m;
		dp[0] = 1, dp[1] = m - n;
		ans = A(m, n);
		for(int i = 2; i <= n; i++) 
			dp[i] = ((m - n) * dp[i - 1] % mod + (i - 1) * (dp[i - 2] + dp[i - 1]) % mod) % mod;
		ans = (ans * dp[n]) % mod;
		cout << ans << '\n'; 
	}
	return 0;
}