#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <queue>
#include <stack>
#include <cmath>
#define LL long long
#define Mod 1000000007
using namespace std;
const int maxn = 200010;

int s[maxn];
const LL mod = 1e9+7;

int main()
{
    s[0] = s[1] = 1;
    for(int i = 2 ; i < 100000 ; i++)
        s[i] = s[i - 1] * i;
    int t;
    LL n,k;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%I64d %I64d",&n,&k);
        LL sum = k * (k+1) / 2;
        if(sum > n)
        {
            printf("-1\n");
            continue;
        }
        LL low = 1;
        LL high = k;
        LL add = (n - sum) / k;
        low += add;
        high += add;
        LL m = (n - sum) % k;
        LL ans = 1;
        for(int i = low ; i <= high ; i++)
        {
            if(i <= high - m)
                ans = (ans * i) % mod;
            else
                ans = (ans * (i + 1))%mod;
        }
        printf("%d\n",ans);
    }

    return 0;
}