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