#include <bits/stdc++.h>
using namespace std;
const long long eps = 10e9 + 1;
string s0 =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
string s1 = "What are you doing while sending \"";
string s2 = "\"? Are you busy? Will you send \"";
string s3 = "\"?";
unsigned long long n, k;
unsigned long long a[100005];
bool flag = false;
void f(int i) {
  if (i == 0) {
    if (k <= s0.length()) {
      cout << s0[k - 1];
      flag = true;
      return;
    }
    k -= s0.length();
    return;
  }
  if (k <= s1.length()) {
    cout << s1[k - 1];
    flag = true;
    return;
  }
  k -= s1.length();
  if (k <= a[i - 1])
    f(i - 1);
  else
    k -= a[i - 1];
  if (flag) return;
  if (k <= s2.length()) {
    cout << s2[k - 1];
    flag = true;
    return;
  }
  k -= s2.length();
  if (k <= a[i - 1])
    f(i - 1);
  else
    k -= a[i - 1];
  if (flag) return;
  if (k <= s3.length()) {
    cout << s3[k - 1];
    flag = true;
    return;
  }
  k -= s3.length();
}
int main() {
  a[0] = 75;
  for (int i = 1; i <= 100000; ++i) a[i] = 68 + a[i - 1] * 2;
  int q;
  cin >> q;
  for (int test = 0; test < q; ++test) {
    flag = false;
    cin >> n >> k;
    f(n);
    if (!flag) cout << ".";
  }
}
