#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, dd, q;
  cin >> n >> dd >> q;
  int arr[200001];
  for (int i = 0; i < 200001; i++) {
    arr[i] = 0;
  }
  for (int h = 0; h < n; h++) {
    int t1, t2;
    cin >> t1 >> t2;
    arr[t1]++;
    arr[t2 + 1]--;
  }
  int count = 0;
  for (int k = 0; k < 200001; k++) {
    count += arr[k];
    arr[k] = count;
  }
  count = 0;
  int ans[200001];
  for (int k = 0; k <= 200000; k++) {
    if (arr[k] >= dd) {
      count++;
    }
    ans[k] = count;
  }
  for (int kk = 0; kk < q; kk++) {
    int r1, r2;
    cin >> r1 >> r2;
    cout << ans[r2] - ans[r1 - 1] << endl;
  }
  return 0;
}
