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#include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a); i <= (b); ++i)
#define ROF(i, a, b) for (int i = (a); i >= (b); --i)
#define all(x) x.begin(),x.end()
#define CLR(i,a) memset(i,a,sizeof(i))
#define fi first
#define se second
#define pb push_back
#define SZ(a) ((int) a.size())
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<ll,ll> pll;
typedef array<ll,3> arr;
typedef double DB;
typedef pair<DB,DB> pdd;
typedef pair<ll,bool> plb;
constexpr ll MAXN=static_cast<ll>(1e5)+10,INF=static_cast<ll>(5e18)+3;
constexpr ll mod=static_cast<ll>(1e9)+7;
ll N,M,T;
ll fact[MAXN],infact[MAXN];
ll binpow(ll a,ll k,const ll &p){
ll res=1;
while(k>0){
if((k&1)==1) res=a*res%p;
a=a*a%p;
k>>=1;
}
return res;
}
inline void solve(){
ll a,b;
cin>>a>>b;
cout<<(fact[a]*infact[b]%mod*infact[a-b])%mod<<"\n";
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
fact[0]=1;
infact[0]=binpow(fact[0],mod-2,mod);;
FOR(i,1,MAXN-5){
fact[i]=(fact[i-1]*i)%mod;
infact[i]=binpow(fact[i],mod-2,mod);
}
#ifdef LOCAL
FOR(i,1,15){
cerr<<fact[i]<<" ";
}
cerr<<"\n";
FOR(i,1,15){
cerr<<infact[i]<<' ';
}
cerr<<"\n";
#endif
cin>>T;
while(T--){
solve();
}
return 0;
}
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