#include <bits/stdc++.h>
using namespace std;
string itosm(long long x) {
  if (x == 0) return "0";
  string res = "";
  while (x > 0) {
    res += ((x % 10) + '0');
    x /= 10;
  }
  reverse(res.begin(), res.end());
  return res;
}
long long stoim(string str) {
  long long res = 0;
  int p = 0;
  if (str[0] == '-') p++;
  for (int i = p; i < str.length(); i++) {
    res *= 10;
    res += (str[i] - '0');
  }
  return res;
}
const long long infll = 1e18 + 3;
const int inf = 1009000999;
const long double eps = 1e-7;
const int maxn = 1e6 + 1146;
const int baseint = 1000200013;
const long long basell = 1e18 + 3;
const long double PI = acos(-1.0);
const long long mod = 1e9 + 9;
vector<pair<double, int> > q;
double ans[maxn];
pair<double, double> t[maxn];
void solve() {
  int sy, a, b;
  cin >> sy >> a >> b;
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    int l, r;
    cin >> l >> r;
    q.push_back({l, 1});
    q.push_back({r, -1});
  }
  int qq;
  cin >> qq;
  for (int i = 0; i < qq; i++) {
    double x, y;
    cin >> x >> y;
    double dx = a - x, dy = y - sy;
    dx *= y / dy;
    t[i].first = dx;
    q.push_back({x + dx, -i - 2});
    dx = b - x;
    dx *= y / dy;
    t[i].second = dx;
    q.push_back({x + dx, i + 2});
  }
  sort(q.begin(), q.end());
  double sum = 0, last = 0;
  for (pair<long double, int> tmp : q) {
    if (tmp.second == 1)
      last = tmp.first;
    else if (tmp.second == -1)
      sum += (tmp.first - last), last = -1;
    else if (tmp.second > 0) {
      ans[tmp.second - 2] += sum;
      if (last > 0) ans[tmp.second - 2] += tmp.first - last;
    } else {
      ans[-tmp.second - 2] -= sum;
      if (last > 0) ans[-tmp.second - 2] -= tmp.first - last;
    }
  }
  cout << fixed << setprecision(7);
  for (int i = 0; i < qq; i++)
    cout << ans[i] / (t[i].second - t[i].first) * (b - a) << "\n";
}
int main() {
  srand(time(0));
  ios_base::sync_with_stdio(0);
  ;
  cin.tie(0);
  cout.tie(0);
  solve();
  return 0;
}
