#include<cmath>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#define inf 1000000000
#define mod 1000000007
using namespace std;
long long cas,x,k,num1,num2,s2,ans,j,i;
long long sqr(long long x)
{return x*x%mod;}
long long ksm(long long x,long long y)
{
    if (!y)return 1;
    if (y==1)return x;
    if (y%2)return sqr(ksm(x,y/2))%mod*x%mod;
    else return sqr(ksm(x,y/2))%mod;
}
int main()
{
    scanf("%I64d",&cas);
    while (cas--)
    {
        scanf("%I64d%I64d",&x,&k);
        if ((1+k)*k/2>x){puts("-1");continue;}
        i=(2*x-k*k+k)/(2*k);
        ans=1;
        s2=x-(i+i+k-1)*k/2;
        for (j=i;j<=i+k-1;j++)
            if (i+k-j<=s2)ans=ans*(j+1)%mod;else ans=ans*j%mod;
        printf("%I64d\n",ans);
    }
}