#include<iostream>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<cstdio>
#include<queue>
#include<stack>
#include<map>
#include<vector>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef double db;
const int maxn=1e6+10;
const int maxm=1e6+10;
const int mod=1e9+7;
const int base=1e8;
const ull base1=233;
const ull base2=19260817;
const int maxxn=0x7fffffff;
const int minxn=-0x7fffffff;
const db inf=1e13;
const db eps=1e-8;
inline ll read(){
    ll x=0,w=1;char c=getchar();
    while(c<'0'||c>'9'){if(c=='-')w=-1;c=getchar();}
    while(c<='9'&&c>='0'){x=(x<<3)+(x<<1)+c-'0';c=getchar();}
    return x*w;
}
int t;
ll fac[maxn],finv[maxn],d[maxn];
inline ll q_pow(ll x,int p){
    ll ans=1;
    while(p){
        if(p&1){
            ans=ans*x%mod;
        }
        x=x*x%mod;
        p>>=1;
    }
    return ans;
}
ll n,m;
int main(){
    t=read();
    fac[0]=finv[0]=1;
    for(int i=1;i<=maxn;i++){
        fac[i]=fac[i-1]*i%mod;
    }
    finv[maxn]=q_pow(fac[maxn],mod-2);
    for(int i=maxn-1;i>=1;i--){
        finv[i]=finv[i+1]*(i+1)%mod;
    }
    d[1]=0,d[2]=1,d[3]=2;
    for(int i=4;i<=maxn;i++){
        d[i]=(i-1)*(d[i-2]+d[i-1])%mod;
    }
    while(t--){
        n=read(),m=read();
        if(m+1==n){
            printf("0\n");
            continue;
        }
        if(m==n){
            printf("1\n");
            continue;
        }
        if(m==0){
            printf("%lld\n",d[n]);
            continue;
        }
        ll ans=fac[n]%mod*finv[m]%mod*finv[n-m]%mod*d[n-m]%mod;
        printf("%lld\n",ans);
    }
    return 0;
}