#include <bits/stdc++.h>
using namespace std;
long long sy, a, b;
int n;
long long L[200005], R[200005];
long long smt[800005];
long long x, y;
void build(int idx, int l, int r) {
  if (l == r) {
    smt[idx] = R[l] - L[l];
    return;
  }
  int m = (l + r) / 2;
  build(idx << 1, l, m);
  build(idx << 1 | 1, m + 1, r);
  smt[idx] = smt[idx << 1] + smt[idx << 1 | 1];
}
long long query(int idx, int l, int r, int s, int t) {
  if (r < s || l > t) return 0;
  if (l >= s && r <= t) return smt[idx];
  int m = (l + r) / 2;
  return query(idx << 1, l, m, s, t) + query(idx << 1 | 1, m + 1, r, s, t);
}
int main() {
  scanf("%lld%lld%lld", &sy, &a, &b);
  sy = -sy;
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%lld%lld", &L[i], &R[i]);
  }
  build(1, 1, n);
  int q;
  scanf("%d", &q);
  while (q--) {
    scanf("%lld%lld", &x, &y);
    int LL, RR;
    int lb = 0, ub = n + 1;
    while (ub > lb + 1) {
      int m = (ub + lb) / 2;
      if ((y + sy) * R[m] - sy * x <= y * a)
        lb = m;
      else
        ub = m;
    }
    LL = ub;
    lb = 0, ub = n + 1;
    while (ub > lb + 1) {
      int m = (ub + lb) / 2;
      if ((y + sy) * L[m] - sy * x >= y * b)
        ub = m;
      else
        lb = m;
    }
    RR = lb;
    if (RR < LL) {
      printf("0\n");
      continue;
    }
    if (RR == LL) {
      long long right = min(b * y, (y + sy) * R[RR] - sy * x);
      long long left = max(a * y, (y + sy) * L[LL] - sy * x);
      printf("%.8f\n", (right - left) * 1.0 / y);
      continue;
    }
    if (RR == LL + 1) {
      long long right1 = min(b * y, (y + sy) * R[RR] - sy * x);
      long long left1 = (y + sy) * L[RR] - sy * x;
      long long right2 = (y + sy) * R[LL] - sy * x;
      long long left2 = max(a * y, (y + sy) * L[LL] - sy * x);
      printf("%.8f\n", (right1 - left1 + right2 - left2) * 1.0 / y);
      continue;
    }
    long long tot = query(1, 1, n, LL + 1, RR - 1);
    long long right1 = min(b * y, (y + sy) * R[RR] - sy * x);
    long long left1 = (y + sy) * L[RR] - sy * x;
    long long right2 = (y + sy) * R[LL] - sy * x;
    long long left2 = max(a * y, (y + sy) * L[LL] - sy * x);
    printf("%.8f\n",
           (right1 - left1 + right2 - left2 + (sy + y) * tot) * 1.0 / y);
  }
  return 0;
}
