#include <bits/stdc++.h>
const int maxn = 100005;
const char f0[] =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
const char fi1[] = "What are you doing while sending \"";
const char fi2[] = "\"? Are you busy? Will you send \"";
const char fi3[] = "\"?";
const int f0len = strlen(f0);
const int fi1len = strlen(fi1);
const int fi2len = strlen(fi2);
const int fi3len = strlen(fi3);
long long len[maxn];
int main() {
  int i = 1, q, n;
  len[0] = f0len;
  long long k;
  scanf("%d", &q);
  while (q--) {
    scanf("%d%I64d", &n, &k);
    for (; i <= n; i++)
      if (len[i - 1] == -1)
        len[i] = -1;
      else {
        len[i] = len[i - 1] * 2 + fi1len + fi2len + fi3len;
        if (len[i] > 1e18) len[i] = -1;
      }
    for (; n; n--)
      if (k <= fi1len) {
        printf("%c", fi1[k - 1]);
        break;
      } else if (k <= fi1len + len[n - 1] || len[n - 1] == -1)
        k -= fi1len;
      else if (k <= fi1len + len[n - 1] + fi2len) {
        printf("%c", fi2[k - fi1len - len[n - 1] - 1]);
        break;
      } else if (k <= fi1len + len[n - 1] + fi2len + len[n - 1])
        k -= fi1len + len[n - 1] + fi2len;
      else if (k <= fi1len + len[n - 1] + fi2len + len[n - 1] + fi3len) {
        printf("%c", fi3[k - fi1len - len[n - 1] - fi2len - len[n - 1] - 1]);
        break;
      } else {
        printf(".");
        break;
      }
    if (!n) printf("%c", (k <= f0len) ? f0[k - 1] : '.');
  }
  printf("\n");
  return 0;
}
