#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 1e5 + 9;
ll L[N], mx = 2e18 + 9;
ll t, n, k;
string f0 =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
string str1 = "What are you doing while sending \"";
string str2 = "\"? Are you busy? Will you send \"";
string str3 = "\"?";
char f(ll n, ll k) {
  if (n == 0) return f0[k];
  if (k < str1.size()) return str1[k];
  k -= str1.size();
  if (k < L[n - 1]) return f(n - 1, k);
  k -= L[n - 1];
  if (k < str2.size()) return str2[k];
  k -= str2.size();
  if (k < L[n - 1]) return f(n - 1, k);
  k -= L[n - 1];
  return str3[k];
}
int main() {
  ios_base ::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  L[0] = f0.size();
  for (int i = 1; i < N; i++) L[i] = min(2LL * L[i - 1] + 68LL, mx);
  cin >> t;
  while (t--) {
    cin >> n >> k;
    k--;
    if (L[n] <= k)
      cout << '.';
    else
      cout << f(n, k);
  }
}
