#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10, LG = 18;
int n, q, par[N][LG], a[N][2];
vector<pair<pair<int, int>, int>> vec;
int main(){
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
memset(par, -1, sizeof par);
cin >> n >> q;
for (int i = 0; i < n; i ++){
int s, e;
cin >> s >> e;
a[i][0] = s, a[i][1] = e;
vec.push_back({{s, 0}, i});
vec.push_back({{e, 1}, i});
}
sort(vec.begin(), vec.end());
set<pair<int, int>> st;
for (auto P : vec){
auto [E, i] = P;
if (!E.second)
st.insert({a[i][1], i});
else{
st.erase({a[i][1], i});
if (st.empty())
par[i][0] = -1;
else{
auto R = *st.rbegin();
par[i][0] = R.second;
}
}
}
for (int j = 1; j < LG; j ++)
for (int i = 0; i < n; i ++)
if (par[i][j - 1] != -1)
par[i][j] = par[par[i][j - 1]][j - 1];
for (int i = 0; i < q; i ++){
int l, r;
cin >> l >> r;
l--, r--;
if (a[r][1] < a[l][1]){
cout << "impossible\n";
continue;
}
if (a[r][1] == a[l][1]){
cout << 1 - (l == r) << '\n';
continue;
}
int cur = l, ans = 0;
for (int j = LG - 1; j >= 0; j --){
if (par[cur][j] == -1) continue;
if (a[par[cur][j]][1] < a[r][1])
cur = par[cur][j], ans += (1 << j);
}
if (par[cur][0] == -1){
cout << "impossible\n";
continue;
}
cout << ans + 1 << '\n';
}
}
