/********************* بسم الله الرحمن الرحيم ***********************/
/******************** ٱلْحَمْدُ لِلَّٰهِ رَبِّ ٱلْعَالَمِينَ *************************/
/******************* Prophet Muhammad صلى الله عليه وسلم ************/
/*********************** وَقُل رَّبِّ زِدْنِي عِلْمًا **************************/
#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
const int M = 1e5 + 1, lg = 17, inf = 1e9+5;
pair<int,int> seg[M*2];
int par[M][lg];
set<pair<int,int>> ms[M];
void modify(int p,int v=0,int s=1,int e=M+1)
{
if (s+1==e)
{
seg[v]=*ms[p].begin();
return;
}
int mid=(s+e)/2,lc=v+1,rc=v+(mid-s)*2;
if (p<mid)
modify(p,lc,s,mid);
else
modify(p,rc,mid,e);
seg[v]=min(seg[lc],seg[rc]);
}
pair<int,int> get(int l,int r,int v=0,int s=1,int e=M+1)
{
if (l>=e or r<=s)
return {inf,0};
if (l<=s && e<=r)
return seg[v];
int mid=(s+e)/2,lc=v+1,rc=v+(mid-s)*2;
return min(get(l,r,rc,mid,e),get(l,r,lc,s,mid));
}
int main()
{
ios::sync_with_stdio(0);
cin.tie(NULL), cout.tie(NULL);
for (int i=0;i<M*2;i++) seg[i]={inf,0},ms[i/2].insert({inf,0});
int n,q;
cin>>n>>q;
int s[n+1]={},e[n+1];
map<int,vector<int>,greater<int>> mp;
set<int> se;
for (int i=1;i<=n;i++)
{
cin>>s[i]>>e[i];
mp[s[i]].push_back(i);
mp[e[i]].push_back(i);
se.insert(e[i]);
}
map<int,int> ind;
for (int i:se)
ind[i]=ind.size();
se.clear();
for (auto [x,v]:mp)
{
for (auto i:v)
if (!se.count(i))
ms[ind[e[i]]].insert({s[i],i}),modify(ind[e[i]]);
for (auto i:v)
if (se.count(i))
{
pair<int,int> p=get(1,ind[e[i]]+1);
if (p.first<s[i])
par[i][0]=p.second;
}
for (auto i:v)
if (se.count(i))
ms[ind[e[i]]].erase({s[i],i}),modify(ind[e[i]]),se.erase(i);
else
se.insert(i);
}
for (int p=1;p<lg;p++)
for (int i=1;i<=n;i++)
par[i][p]=par[par[i][p-1]][p-1];
while (q--)
{
int x,y;
cin>>x>>y;
if (x==y)
cout<<0<<endl;
else if(s[y]<=e[x] && e[x]<=e[y])
cout<<1<<endl;
else if(e[x]>e[y])
cout<<"impossible"<<endl;
else
{
int ans=2,dm=y;
for (int p=lg-1;p>=0;p--)
if (s[par[dm][p]]>e[x])
dm=par[dm][p],ans+=(1<<p);
if (par[dm][0])
cout<<ans<<endl;
else
cout<<"impossible"<<endl;
}
}
return 0;
}
