#include <bits/stdc++.h>
using namespace std;
const long long INF = 1e18 + 7;
long long f[200009];
string f0 =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
string a = "What are you doing while sending \"";
string b = "\"? Are you busy? Will you send \"";
string c = "\"?";
char solve(long long n, long long k) {
  if (n == 0) return f0[k - 1];
  if (k <= a.size())
    return a[k - 1];
  else if (k <= a.size() + f[n - 1])
    return solve(n - 1, k - a.size());
  else if (k <= a.size() + f[n - 1] + b.size())
    return b[k - (a.size() + f[n - 1]) - 1];
  else if (k <= a.size() + f[n - 1] + b.size() + f[n - 1])
    return solve(n - 1, k - (a.size() + f[n - 1] + b.size()));
  else
    return c[k - (a.size() + f[n - 1] + b.size() + f[n - 1]) - 1];
}
int main() {
  f[0] = f0.size();
  for (int i = 1; i < 200009; i++) {
    f[i] = a.size() + f[i - 1] + b.size() + f[i - 1] + c.size();
    f[i] = min(f[i], INF);
  }
  int tt;
  cin >> tt;
  while (tt--) {
    long long n, k;
    cin >> n >> k;
    if (f[n] < k) {
      cout << ".";
    } else {
      cout << solve(n, k);
    }
  }
  cout << endl;
  return 0;
}
