#include <bits/stdc++.h>
template <class C, class E>
inline bool contains(const C& container, const E& element) {
  return container.find(element) != container.end();
}
template <class T>
inline void checkmin(T& a, T b) {
  if (b < a) a = b;
}
template <class T>
inline void checkmax(T& a, T b) {
  if (b > a) a = b;
}
using namespace std;
vector<pair<long long, long long> > obs;
vector<long long> sombrasSum;
int sy, aa, bb, n;
double Suma(int from, int to) {
  if (from > to) return 0;
  if (from >= n) return 0;
  if (to < 0) return 0;
  return sombrasSum[to + 1] - sombrasSum[from];
}
double ProyectFenceToLuz(pair<long long, long long> p, long long fx) {
  return (double)fx + (double)sy * (double)(p.first - fx) / (double)p.second;
}
double ProyectLuzToFence(pair<long long, long long> p, long long l) {
  return (double)l -
         (double)sy * (double)(p.first - l) / ((double)p.second - (double)sy);
}
double Process(pair<long long, long long> f, pair<long long, long long> p) {
  double s = ProyectFenceToLuz(p, f.first);
  double e = ProyectFenceToLuz(p, f.second);
  checkmin(s, (double)bb);
  checkmax(s, (double)aa);
  checkmin(e, (double)bb);
  checkmax(e, (double)aa);
  return e - s;
}
void Solve(pair<long long, long long> p) {
  double apd = ProyectLuzToFence(p, aa) - 1;
  double bpd = ProyectLuzToFence(p, bb) + 1;
  checkmin(apd, 1000000000.0);
  checkmin(bpd, 1000000000.0);
  checkmax(apd, 0.0);
  checkmax(bpd, 0.0);
  long long ap = apd, bp = bpd;
  int fa = upper_bound((obs).begin(), (obs).end(), make_pair(ap, -1LL)) -
           obs.begin();
  int fb = upper_bound((obs).begin(), (obs).end(), make_pair(bp, -1LL)) -
           obs.begin();
  if (fa != 0) --fa;
  if (fb == n) --fb;
  double res = 0;
  for (int i = (0), _b = ((3) - 1); i <= _b; i++) {
    if (fa < n && fa <= fb) {
      res += Process(obs[fa], p);
      ++fa;
    }
  }
  for (int i = (0), _b = ((3) - 1); i <= _b; i++) {
    if (fb >= 0 && fb < n && fb >= fa) {
      res += Process(obs[fb], p);
      --fb;
    }
  }
  double scale = (double)(-sy + p.second) / (double)p.second;
  cout << res + Suma(fa, fb) * scale << endl;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cout << std::setprecision(15);
  cout << std::fixed;
  cin >> sy >> aa >> bb >> n;
  obs.resize(n);
  sombrasSum.resize(n + 1);
  for (int i = (0), _b = ((n)-1); i <= _b; i++) {
    cin >> obs[i].first >> obs[i].second;
    sombrasSum[i + 1] = sombrasSum[i] + (obs[i].second - obs[i].first);
  }
  int q;
  cin >> q;
  for (int i = (0), _b = ((q)-1); i <= _b; i++) {
    pair<long long, long long> p;
    cin >> p.first >> p.second;
    Solve(p);
  }
  return 0;
}
