#include <bits/stdc++.h>
using namespace std;
int N, D;
signed long long A[202020];
int M;
void solve() {
  int i, j, k, l, r, x, y;
  string s;
  cin >> N >> D;
  for (i = 0; i < (N); i++) cin >> A[i];
  cin >> M;
  for (i = 0; i < (M); i++) {
    cin >> x;
    if (x == A[0] || x == A[N - 1] + 1) {
      (void)printf("%.12lf\n", atan(1) * 2);
      continue;
    }
    y = lower_bound(A, A + N, x) - A;
    if (A[y] == x && A[y - 1] == x - 1) {
      (void)printf("%.12lf\n", atan(1) * 4);
      continue;
    }
    if (A[y] == x || A[y - 1] == x - 1) {
      (void)printf("%.12lf\n", atan(1) * 2);
      continue;
    }
    signed long long dif = min(x - A[y - 1] - 1, A[y] - x);
    double ret = atan(1.0 / dif);
    int L = y - 1;
    int R = y;
    int ok = 0;
    for (j = 20; j >= 0; j--)
      if (2 * atan(1.0 / (ok + (1 << j))) >= ret) ok += 1 << j;
    while (L >= 0 && R < N) {
      int dl = x - (A[L] + 1);
      int dr = A[R] - x;
      if (max(dl, dr) > ok) break;
      if (abs(dl - dr) <= 1) {
        ret = 2 * atan(1.0 / max(dl, dr));
        break;
      }
      if (dl < dr)
        L--;
      else
        R++;
    }
    (void)printf("%.12lf\n", ret);
  }
}
int main(int argc, char** argv) {
  string s;
  int i;
  if (argc == 1) ios::sync_with_stdio(false), cin.tie(0);
  for (i = 0; i < (argc - 1); i++) s += argv[i + 1], s += '\n';
  for (i = 0; i < (s.size()); i++) ungetc(s[s.size() - 1 - i], stdin);
  cout.tie(0);
  solve();
  return 0;
}
