#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 10 , L = 18;
int n , q , l[N] , r[N] , mv[L][N];
vector <int> vec , st;
bool cmp(int a , int b) {
if(r[a] != r[b]) return r[a] < r[b];
return l[a] < l[b];
}
int Bs(int x){
int low = -1 , high = st.size();
while(high - low > 1) {
int mid = (low + high) >> 1;
if(r[st[mid]] >= x) high = mid;
else low = mid;
}
return st[high];
}
int solve(int from , int to , int bit) {
if(bit == -1) return 0;
int nex = mv[bit][from];
if(l[nex] > r[to]) return (1 << bit) + solve(nex , to , bit - 1);
return solve(from , to , bit - 1);
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
cin >> n >> q;
for(int i = 1 ; i <= n ; i++) {
cin >> l[i] >> r[i];
vec.push_back(i);
}
sort(vec.begin() , vec.end() , cmp);
for(int i = 1 ; i <= n ; i++) {
int now = vec[i];
while(!st.empty() && l[st.back()] >= l[now]) st.pop_back();
st.push_back(now);
mv[0][now] = Bs(l[now]);
}
for(int i = 1 ; i < L ; i++) for(int j = 1 ; j <= n ; j++) mv[i][j] = mv[i - 1][mv[i - 1][j]];
while(q--) {
int s , e; cin >> s >> e;
if(l[mv[L - 1][e]] > r[s] || r[e] < r[s]) {
cout << "impossible" << '\n';
continue;
}
if(s == e) {
cout << 0 << '\n';
continue;
}
if(l[e] <= r[s]) {
cout << 1 << '\n';
continue;
}
cout << solve(e , s , L - 1) + 2 << '\n';
}
}
