#include <bits/stdc++.h>
using namespace std;
const int M = 1000000007;
const int MM = 998244353;
const long double PI = acos(-1);
long long power(long long b, long long e, long long m) {
  if (e == 0) return 1;
  if (e & 1) return b * power(b * b % m, e / 2, m) % m;
  return power(b * b % m, e / 2, m);
}
long long power(long long b, long long e) {
  if (e == 0) return 1;
  if (e & 1) return b * power(b * b, e / 2);
  return power(b * b, e / 2);
}
template <typename T, typename U>
static inline void amin(T &x, U y) {
  if (y < x) x = y;
}
template <typename T, typename U>
static inline void amax(T &x, U y) {
  if (x < y) x = y;
}
template <typename T, typename U>
ostream &operator<<(ostream &os, const pair<T, U> &p) {
  return os << '(' << p.first << "," << p.second << ')';
}
const int N = 200005;
int r[N], lenr[N];
int rnk[N], p[N];
int parent(int i) { return p[i] = (p[i] == i) ? i : parent(p[i]); }
void merge(int x, int y) {
  x = parent(x), y = parent(y);
  if (x == y) return;
  if (rnk[x] > rnk[y]) swap(x, y);
  if (rnk[x] == rnk[y]) ++rnk[y];
  p[x] = y;
  amax(r[y], r[x]);
  amax(lenr[y], lenr[x]);
}
int px[N], lx[N];
struct Qu {
  int x, y, i;
};
template <typename T = long long>
struct fenwick {
  T a[N], bit[N];
  int n;
  fenwick() {
    for (int i = 1; i <= N - 2; ++i) a[i] = T(0), bit[i] = T(0);
  }
  void build(int n_) {
    n = n_;
    for (int i = 1; i <= n; ++i)
      for (int j = i; j <= n; j += j & -j) bit[j] += a[i];
  }
  void update(int j, T val) {
    int pos = j;
    for (; j <= n; j += j & -j) bit[j] += val - a[pos];
    a[pos] = val;
  }
  T get(int r) {
    T u = 0;
    for (; r; r -= r & -r) u += bit[r];
    return u;
  }
  T query(int l, int r) { return get(r) - get(l - 1); }
};
fenwick<int> fenw;
int ans[N];
int _runtimeTerror_() {
  int n;
  cin >> n;
  for (int i = 1; i <= n; ++i) {
    cin >> px[i] >> lx[i];
    p[i] = i;
    r[i] = i;
    lenr[i] = px[i] + lx[i];
  }
  int Q;
  cin >> Q;
  vector<Qu> q(Q);
  int curr = Q - 1;
  for (int i = 0; i < Q; ++i) {
    cin >> q[i].x >> q[i].y;
    q[i].i = i;
  }
  sort(q.begin(), q.end(), [&](Qu a, Qu b) { return a.x < b.x; });
  fenw.build(n);
  for (int i = n - 1; i >= 1; --i) {
    int cur = i;
    fenw.update(cur + 1, px[cur + 1] - lenr[cur]);
    while (cur < n && lenr[parent(cur)] >= px[cur + 1]) {
      fenw.update(cur + 1, 0);
      merge(cur, cur + 1);
      cur = r[parent(cur)];
    }
    fenw.update(cur + 1, px[cur + 1] - lenr[parent(cur)]);
    while (curr >= 0 && q[curr].x == i) {
      ans[q[curr].i] = fenw.query(i, q[curr].y);
      --curr;
    }
  }
  for (int i = 0; i < Q; ++i) cout << ans[i] << "\n";
  return 0;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int TESTS = 1;
  while (TESTS--) _runtimeTerror_();
  return 0;
}
