#include <bits/stdc++.h>
using namespace std;
const long long int mod = 1e9 + 7;
bool IsPowerOfTwo(long long int x) { return (x != 0) && ((x & (x - 1)) == 0); }
long long int poer(long long int a, long long int b) {
  long long int rs = 1;
  while (b > 0) {
    if (b & 1) rs *= a;
    a *= a;
    b /= 2;
  }
  return rs;
}
long long int mod_poer(long long int a, long long int b, long long int mo) {
  long long int rs = 1;
  while (b > 0) {
    if (b & 1) rs = (rs * a) % mo;
    a = (a * a) % mo;
    b /= 2;
  }
  return rs % mo;
}
long long int d, x, y;
void ext_euclid(long long int a, long long int b) {
  if (b == 0) {
    d = a;
    x = 1;
    y = 0;
  } else {
    ext_euclid(b, a % b);
    long long int temp = x;
    x = y;
    y = temp - (a / b) * y;
  }
}
long long int mod_inverse1(long long int a, long long int m) {
  ext_euclid(a, m);
  return (x % m + m) % m;
}
long long int mod_inverse2(long long int a, long long int m) {
  return mod_poer(a, m - 2, m);
}
long long int gcd(long long int a, long long int b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
long long int fact[200005];
void fac() {
  fact[1] = fact[0] = 1;
  for (long long int i = 2; i <= 200005; ++i) {
    fact[i] = ((fact[i - 1] % mod) * i) % mod;
  }
}
long long int combi(long long int a, long long int b) {
  if (b > a) return 0;
  if (b == a)
    return 1;
  else {
    long long int x = mod_poer(fact[b], mod - 2, mod) % mod;
    long long int y = mod_poer(fact[a - b], mod - 2, mod) % mod;
    return ((((fact[a]) * x) % mod) * y) % mod;
  }
}
long long int len[54];
string str1 = "What are you doing while sending \"";
string str2 = "\"? Are you busy? Will you send \"";
string str3 = "\"?";
long long int len1 = str1.size();
long long int len2 = str2.size();
long long int len3 = str3.size();
string f0 =
    "What are you doing at the end of the world? Are you busy? Will you save "
    "us?";
char get(long long int n, long long int k) {
  if (n > 54) {
    if (k <= len1) return str1[k - 1];
    return get(n - 1, k - len1);
  }
  if (n < 54 && k > len[n]) return '.';
  if (n == 0) return f0[k - 1];
  if (k <= len1) return str1[k - 1];
  if (k <= len1 + len[n - 1]) return get(n - 1, k - len1);
  if (k <= len1 + len[n - 1] + len2) return str2[k - len1 - len[n - 1] - 1];
  if (k <= len1 + len[n - 1] * 2 + len2)
    return get(n - 1, k - len1 - len[n - 1] - len2);
  return str3[k - len1 - len[n - 1] * 2 - len2 - 1];
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  len[0] = f0.size();
  for (long long int i = 1; i < 54; ++i) {
    len[i] = (len[i - 1] * 2) + len1 + len2 + len3;
  }
  long long int t;
  cin >> t;
  while (t--) {
    long long int n, k;
    cin >> n >> k;
    cout << get(n, k);
  }
  cout << "\n";
  return 0;
}
