#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define no "impossible\n"
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
// --s1-------e1------
// -----s2-------e2---
// --s3------e3-------
// -------s4-------e4-
int N, Q;
cin >> N >> Q;
vector<pair<int, int>> a(N);
vector<int> b;
for(int i = 0; i < N; i++) {
cin >> a[i].first >> a[i].second;
b.push_back(a[i].second);
}
ranges::sort(b);
b.erase(unique(b.begin(), b.end()), b.end());
const int LOG = 17;
const int inf = 1e9 + 5;
vector rmq(LOG, vector<pair<int, int>>(N, {inf, -1}));
for(int i = 0; i < N; i++) {
int r = ranges::lower_bound(b, a[i].second) - b.begin();
rmq[0][r] = min(rmq[0][r], {a[i].first, i});
}
for(int i = 0; i + 1 < LOG; i++)
for(int j = 0; j + (1 << (i + 1)) <= N; j++)
rmq[i + 1][j] = min(rmq[i][j], rmq[i][j + (1 << i)]);
vector up(LOG, vector<int>(N));
for(int i = 0; i < N; i++) {
int l = ranges::lower_bound(b, a[i].first) - b.begin();
int r = ranges::lower_bound(b, a[i].second) - b.begin();
int h = __lg(r - l + 1);
up[0][i] = min(rmq[h][l], rmq[h][r + 1 - (1 << h)]).second;
}
for(int i = 0; i + 1 < LOG; i++)
for(int j = 0; j < N; j++)
up[i + 1][j] = up[i][up[i][j]];
while(Q--) {
int s, e;
cin >> s >> e, s--, e--;
int l = 1;
if(s == e || a[e].first <= a[s].second && a[s].second <= a[e].second) {
cout << (s == e ? 0 : 1) << "\n";
continue;
}
for(int i = LOG; i--;) {
if(a[s].second < a[up[i][e]].first)
l += 1 << i, e = up[i][e];
}
e = up[0][e];
if(a[s].second < a[e].first || a[s].second > a[e].second)
cout << no;
else
cout << l + (a[s].second >= a[e].first) << "\n";
}
return 0;
}
