#include<cstdio>
#include<cstdlib>
#include<time.h>
#include<cmath>
#include<cstring>
#include<string>
#include<iostream>
#include<queue>
#include<map>
#include<set>
#include<stack>
#include<vector>
#include<algorithm>

//#include<bits/c++std.h>

#define Size 100005
#define inf 2e9
#define INF 2e18
#define LL long long
#define i64 __int64
#define ULL unsigned long long
#define Mod 1000000007

using namespace std;
LL n,m,k;

int main()
{
    #ifndef ONLINE_JUDGE
//        freopen("input.txt","r",stdin);
//        freopen("output.txt","w",stdout);
    #endif // ONLINE_JUDGE
    LL t;
    LL x,y,z;
//    LL Case=0;
    cin>>t;
    while(t--)
//    cin>>n;
//    while(scanf("%I64d%I64d",&n,&m)==2)
    {
        cin>>n>>k;
        if(n < (k+1)*k/2)
        {
            cout<<-1<<endl;
        }
        else
        {
            LL ans = 1;
            LL tmp = (k+1)*k/2;
            LL tmp2 = n - tmp;
            LL tmp3 = tmp2/k;
            LL tmp4 = tmp2%k;
            for(LL i=1 ;i<=k ;++i)
            {
                if(i+tmp4<=k)
                {ans *= (tmp3 + i)%Mod;
                ans %= Mod;
                }
                else
                {
                    ans *= (tmp3+i+1)%Mod;
                    ans %= Mod;
                }
            }
            cout<<ans<<endl;
        }
    }
    return 0;
}