#include <bits/stdc++.h>
using namespace std;
char cd[] =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
char czz[3][1000] = {"What are you doing while sending \"",
                     "\"? Are you busy? Will you send \"", "\"?"};
int cdn, czzn[3];
long long cds[100010];
void _cl(int n, long long dk) {
  if (!n) {
    if (dk > cdn)
      putchar('.');
    else {
      putchar(cd[dk - 1]);
    }
  } else {
    int i, j, k;
    if (dk <= czzn[0])
      putchar(czz[0][dk - 1]);
    else {
      dk -= czzn[0];
      if (cds[n - 1] < 0 || cds[n - 1] >= dk)
        _cl(n - 1, dk);
      else {
        dk -= cds[n - 1];
        if (dk <= czzn[1])
          putchar(czz[1][dk - 1]);
        else {
          dk -= czzn[1];
          if (cds[n - 1] < 0 || cds[n - 1] >= dk)
            _cl(n - 1, dk);
          else {
            dk -= cds[n - 1];
            if (dk <= czzn[2])
              putchar(czz[2][dk - 1]);
            else
              putchar('.');
          }
        }
      }
    }
  }
};
void cl() {
  int i, j, k;
  int n;
  long long dk;
  cdn = strlen(cd);
  for (i = 0; i < 3; ++i) czzn[i] = strlen(czz[i]);
  cin >> n >> dk;
  for (cds[0] = cdn, i = 1; i <= 100000; ++i) {
    double tx = 2.0 * (double)cds[i - 1] + czzn[0] + czzn[1] + czzn[2];
    if (tx > dk) break;
    cds[i] = 2 * cds[i - 1] + czzn[0] + czzn[1] + czzn[2];
  }
  for (; i <= 100000; ++i) cds[i] = -1;
  _cl(n, dk);
};
int main() {
  int t;
  scanf("%d", &t);
  while (t--) cl();
  return 0;
};
