#define IOS ios_base::sync_with_stdio(0); cin.tie(0);

 #include <cstdio>//sprintf islower isupper

 #include <cstdlib>//malloc  exit strcat itoa system("cls")

 #include <iostream>//pair

 #include <fstream>

 #include <bitset>

 //#include <map>

 //#include<unordered_map>

 #include <vector>

 #include <stack>

 #include <set>

 #include <string.h>//strstr substr

 #include <string>

 #include <time.h>//srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;

 #include <cmath>

 #include <deque>

 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less

 #include <vector>//emplace_back

 //#include <math.h>

 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor

 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)

 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation

 #define mem(a,b) memset(a,b,sizeof(a))

 #define fo(a,b,c) for(a=b;a<=c;++a)//register int i

 #define fr(a,b,c) for(a=b;a>=c;--a)

 #define pr printf

 #define sc scanf

 void swapp(int &a,int &b);

 double fabss(double a);

 int maxx(int a,int b);

 int minn(int a,int b);

 int Del_bit_1(int n);

 int lowbit(int n);

 int abss(int a);

 //const long long INF=(1LL<<60);

 const double E=2.718281828;

 const double PI=acos(-1.0);

 const int inf=(<<);

 const double ESP=1e-;

 const int mod=(int)1e9+;

 const int N=(int)1e6+;

 long long qpow(long long a,long long b,long long mod)

 {

     long long ans;

     a%=mod;

     ans=;

     while(b!=)

     {

         if(b&)

             ans=(ans*a)%mod;

         b/=;

         a=(a*a)%mod;

     }

     return ans;

 }

 int main()

 {

     int T;

     sc("%d",&T);

     long long ans=,res;

     while(T--)

     {

         long long n,m;

         sc("%lld%lld",&n,&m);

         if(n==)

         {

             res=;

         }

         else

         {

             if(m==)

             {

                 res=;

             }

             else

                 res=qpow(n-,mod-,mod);

         }

         ans=ans*res;

         ans%=mod;

         pr("%lld\n",ans);

     }

     return ;

 }

 /**************************************************************************************/

 int maxx(int a,int b)

 {

     return a>b?a:b;

 }

 void swapp(int &a,int &b)

 {

     a^=b^=a^=b;

 }

 int lowbit(int n)

 {

     return n&(-n);

 }

 int Del_bit_1(int n)

 {

     return n&(n-);

 }

 int abss(int a)

 {

     return a>?a:-a;

 }

 double fabss(double a)

 {

     return a>?a:-a;

 }

 int minn(int a,int b)

 {

     return a<b?a:b;

 }