#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cstdlib>
#include <memory.h>
#define MOD 1000000007
using namespace std;

long long ans[100010];
int l;
int main() {
    int T;
    scanf("%d",&T);
    while (T --) {
        int n,k;
        scanf("%d%d",&n,&k);
        if (1LL * k * (k + 1) / 2 > n) puts("-1");
        else {
            for (int i = 1;i <= k;i ++) ans[i] = i;
            n -= (1LL * k * (k + 1) / 2);
            for (int i = 1;i <= k;i ++) ans[i] += n / k;
            n %= k;
            l=k;
            while (n) ans[l] ++,n --,l --;
            int res = 1;
            for (int i = 1;i <= k;i ++) res = 1LL * res * ans[i] % MOD;
            printf("%d\n",res);
        }
    }
}