#include <bits/stdc++.h>
using namespace std;
#define all(a) a.begin(),a.end()
#define owo ios_base::sync_with_stdio(0);cin.tie(0);
const int MAXN = 1e5+1;
int s[MAXN],e[MAXN];
int main()
{
owo
int n,q;
cin>>n>>q;
vector<int>crd;
for(int i=0;i<n;i++)cin>>s[i]>>e[i];
for(int i=0;i<n;i++){
crd.push_back(s[i]);
crd.push_back(e[i]);
}
sort(all(crd));
crd.resize(unique(all(crd)) - crd.begin());
for(int i=0;i<n;i++){
s[i] = lower_bound(all(crd),s[i]) - crd.begin()+1;
e[i] = lower_bound(all(crd),e[i]) - crd.begin()+1;
}
int m = crd.size();
vector<int>mn(m+1);
for(int i=1;i<=m;i++)mn[i] = i;
for(int i=0;i<n;i++){
mn[e[i]] = min(mn[e[i]],s[i]);
}
//cout<<"range"<<'\n';
//for(int i=0;i<n;i++)cout<<s[i]<<" "<<e[i]<<'\n';
//for(int i=1;i<=m;i++)cout<<mn[i]<<" ";
//cout<<'\n';
//greedy backwards
//forward fails because we are going to exact nodes
while(q--){
int l,r;
cin>>l>>r;
l--;
r--;
if(l==r){
cout<<0<<'\n';
continue;
}
if(e[l] > e[r]){
cout<<"impossible"<<'\n';
continue;
}
int cur = s[r];
int last = e[r];
int ans = 1;
while(cur > e[l]){
int best = cur;
for(int i=cur;i<=last;i++)best = min(best,mn[i]);
if(best == cur){
ans = -1;
break;
}
last = cur;
cur = best;
ans++;
}
if(ans==-1)cout<<"impossible"<<'\n';
else cout<<ans<<'\n';
}
}
