#include <bits/stdc++.h>
using namespace std;
string f0 =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
string x = "What are you doing while sending \"";
string y = "\"? Are you busy? Will you send \"";
string z = "\"?";
long long t, nn;
long long kk;
long long num[100001];
char solve(long long n, long long k) {
  if (k >= num[n]) return '.';
  if (n == 0) return f0[k];
  if (k < x.size()) return x[k];
  k -= x.size();
  if (k < num[n - 1]) return solve(n - 1, k);
  k -= num[n - 1];
  if (k < y.size()) return y[k];
  k -= y.size();
  if (k < num[n - 1]) return solve(n - 1, k);
  k -= num[n - 1];
  if (k < z.size()) return z[k];
}
int main() {
  num[0] = f0.size();
  for (int i = 1; i <= 55; i++)
    num[i] = x.size() + 2 * num[i - 1] + y.size() + z.size();
  for (int j = 56; j <= 100000; j++) num[j] = LLONG_MAX;
  for (cin >> t; t--;) cin >> nn >> kk, cout << solve(nn, kk - 1);
}
