//g++ 1.cpp -std=c++14 -O2 -I .
#include <bits/stdc++.h>
using namespace std;

#include <atcoder/all>
using namespace atcoder;

#include<boost/multiprecision/cpp_int.hpp>
using namespace boost::multiprecision;

using ll = long long;
using ld = long double;

using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vld = vector<ld>;
using vvld = vector<vld>;
using vst = vector<string>;
using vvst = vector<vst>;

#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define pq_big(T) priority_queue<T,vector<T>,less<T>>
#define pq_small(T) priority_queue<T,vector<T>,greater<T>>
#define all(a) a.begin(),a.end()
#define rep(i,start,end) for(ll i=start;i<(ll)(end);i++)
#define per(i,start,end) for(ll i=start;i>=(ll)(end);i--)
#define uniq(a) sort(all(a));a.erase(unique(all(a)),a.end())

cpp_int mpower(cpp_int a,cpp_int b,cpp_int c){
  cpp_int z;
  if(b==0){
    z=1;
    z%=c;
    return z;
  }
  if(b==1){
    z=a;
    z%=c;
    return z;
  }
  if(b%2==0){
    z=mpower(a,b/2,c);
    return (z*z)%c;
  }
  else{
    z=mpower(a,b-1,c);
    return (z*mpower(a,1,c))%c;
  }
}

void solve(){
  cpp_int a,b,c;
  cin>>a>>b>>c;

  cpp_int t=mpower(10,c,10*b);
  t*=a;
  t/=b;
  cout<<t%10<<endl;
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  int t;
  cin>>t;

  while(t--){
    solve();
  }
}