#include<bits/stdc++.h>
using namespace std;
#define task "task"
#define ii pair<int,int>
#define fi first
#define se second
//#define int long long
#define ll long long
#define ld double
#define mp make_pair
#define lg2 20
#define iii pair<int,ii>
#define iiii pair<ii,ii>
#define base 29
#define eps 1e-8
int dx[]= {0LL,0LL,1,-1,1,1,-1,-1};
int dy[]= {1,-1,0LL,0LL,1,-1,1,-1};
const int maxn=4e5+1;
const int mod=1e9+7;
int n,q,s[maxn],e[maxn],sz,P[maxn][lg2+1];
vector<int>nen;
ii tree[4*maxn];
void update(int i,ii val,int id=1,int l=1,int r=sz)
{
if(l==r)
{
tree[id]=min(tree[id],val);
return;
}
int mid=(l+r)/2;
if(i<=mid)
update(i,val,id*2,l,mid);
else update(i,val,id*2+1,mid+1,r);
tree[id]=min(tree[id*2],tree[id*2+1]);
}
ii get(int u,int v,int id=1,int l=1,int r=sz)
{
if(u>r||v<l)return mp(1e9,1e9);
if(u<=l&&v>=r)return tree[id];
int mid=(l+r)/2;
return min(get(u,v,id*2,l,mid),get(u,v,id*2+1,mid+1,r));
}
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
if(fopen(task".inp","r"))
{
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
cin>>n>>q;
for(int i=1;i<=n;i++)
{
cin>>s[i]>>e[i];
nen.push_back(s[i]);
nen.push_back(e[i]);
}
sort(nen.begin(),nen.end());
nen.erase(unique(nen.begin(),nen.end()),nen.end());
sz=nen.size();
memset(tree,0x3f,sizeof(tree));
for(int i=1;i<=n;i++)
{
int l=lower_bound(nen.begin(),nen.end(),s[i])-nen.begin()+1;
int r=lower_bound(nen.begin(),nen.end(),e[i])-nen.begin()+1;
update(r,mp(s[i],i));
}
for(int i=1;i<=n;i++)
{
int l=lower_bound(nen.begin(),nen.end(),s[i])-nen.begin()+1;
int r=lower_bound(nen.begin(),nen.end(),e[i])-nen.begin()+1;
P[i][0]=get(l,r).se;
}
for(int j=1;j<=lg2;j++)
{
for(int i=1;i<=n;i++)
{
P[i][j]=P[P[i][j-1]][j-1];
}
}
while(q--)
{
int l,r;
cin>>l>>r;
if(l==r)
{
cout<<0<<'\n';
continue;
}
if(e[l]>e[r])
{
cout<<"impossible"<<'\n';
continue;
}
if(e[l]>=s[r])
{
cout<<1<<'\n';
continue;
}
int ans=2;
for(int i=lg2;i>=0;i--)
{
if(s[P[r][i]]>e[l])
{
ans+=(1<<i);
r=P[r][i];
}
}
r=P[r][0];
if(s[r]>e[l])
{
cout<<"impossible"<<'\n';
continue;
}
cout<<ans<<'\n';
}
cerr <<endl<< "TIME : " << clock() * 0.001 << "s" << endl ;
}
