#include <bits/stdc++.h>
using namespace std;
int main() {
  long long l[100000 + 100];
  l[0] = 75;
  int i;
  for (i = 1; i < 100; ++i) {
    l[i] = l[i - 1] * 2 + 34 + 32 + 2;
    if (l[i] > 1000000000000000000LL) break;
  }
  for (; i < 100000 + 100; ++i) {
    l[i] = 1000000000000000100LL;
  }
  int q;
  scanf("%d", &q);
  char A[] = "\0What are you doing while sending \"";
  char B[] = "\0\"? Are you busy? Will you send \"";
  char C[] = "\0\"?";
  char S[] =
      "\0What are you doing at the end of the world? Are you busy? Will you "
      "save us?";
  char res[50];
  int pos = 0;
  while (q--) {
    long long n, k;
    scanf("%lld%lld", &n, &k);
    char ans;
    while (1) {
      if (n == 0) {
        if (k <= 75)
          ans = S[k];
        else
          ans = '.';
        break;
      }
      if (k <= 34) {
        ans = A[k];
        break;
      } else if (k <= 34 + l[n - 1]) {
        k -= 34;
        n -= 1;
      } else if (k <= 34 + l[n - 1] + 32) {
        ans = B[k - 34 - l[n - 1]];
        break;
      } else if (k <= 34 + 2 * l[n - 1] + 32) {
        k -= 34 + l[n - 1] + 32;
        n--;
      } else if (k <= l[n]) {
        ans = C[k - (34 + 2 * l[n - 1] + 32)];
        break;
      } else {
        ans = '.';
        break;
      }
    }
    res[pos++] = ans;
  }
  res[pos] = 0;
  printf("%s\n", res);
  return 0;
}
