// CODIGO DA ESTELA!!!!! (eu ajudei talvez)
#include <bits/stdc++.h>
using namespace std;
typedef pair<int,int> ii;
typedef pair<int,ii> iii;
const int maxx = 1e9+5;
const int LOG = 20;
vector<ii> tree;
void update(int pos, int i, int f, int idx, int val, int id){
if(i == f){
tree[pos] =min(tree[pos], {val,id});
return;
}
int meio = (i+f)/2;
if(idx <= meio) update(2*pos+1, i, meio, idx, val, id);
else update(2*pos+2, meio + 1, f, idx, val, id);
tree[pos] = min(tree[2*pos+1], tree[2*pos+2]);
return;
}
ii query(int pos, int i, int f, int l, int r){
if(l<=i and f<=r) return tree[pos];
int meio = (i+f)/2;
ii aa = {maxx, -1};
if(l <=meio) aa = min(aa, query(2*pos+1, i, meio, l, r));
if( r > meio) aa = min(aa, query(2*pos+2, meio + 1, f, l, r));
return aa;
}
int main(){
int n,q; cin >> n >> q;
vector<ii> v(n+2);
vector<iii> event;
tree.resize(8*n, {maxx, -1});
set<int> S;
for(int i=1; i<=n; i++){
int s,e; cin >> s >> e;
v[i] = {s,e};
S.insert(s);
S.insert(e);
}
map<int,int> COMP;
for(auto i: S){
COMP[i] = COMP.size();
}
for(auto &[a,b]: v) {a = COMP[a]; b = COMP[b];}
for(int i=1; i<=n; i++){ event.push_back({v[i].first, {0,i}}); event.push_back({v[i].second, {1,i}}); update(0,0,COMP.size(), v[i].second, v[i].first, i);}
sort(event.begin(), event.end());
set<ii> aux;
vector sparse1(n+2, vector (LOG,0));
for(auto [t,b]: event){
auto [type,idx] = b;
if(!type) aux.insert({v[idx].second, idx});
else{
auto [maior, i] = *prev(aux.end());
sparse1[idx][0] = i;
aux.erase({t, idx});
}
}
for(int i=1; i<LOG; i++) for(int j = 1; j<=n; j++){
sparse1[j][i] = sparse1[sparse1[j][i-1]][i-1];
}
vector sparse2(n+2, vector (LOG,0));
for(int i=1; i<=n; i++){
sparse2[i][0] = query(0,0,COMP.size(), v[i].first, v[i].second).second;
}
for(int i=1; i<LOG; i++) for(int j = 1; j<=n; j++){
sparse2[j][i] = sparse2[sparse2[j][i-1]][i-1];
}
while(q--){
int s,e; cin >> s >> e;
if(s==e){cout << 0 << endl; continue;}
if(v[e].first <= v[s].second && v[s].second <= v[e].second) {
cout <<1 << endl;
continue;
}
int ss = s, ee = e;
int qnt = 0;
for(int i = LOG - 1; i>=0; i--){
int idx = sparse1[ss][i];
if(v[idx].second >= v[e].first) continue;
ss = idx;
qnt += (1<<i);
}
for(int i = LOG - 1; i>=0; i--){
int idx = sparse2[ee][i];
if(v[idx].first > v[ss].second){
ee = idx;
qnt += (1<<i);
}
}
ee = sparse2[ee][0];
qnt++;
if(v[ee].first <= v[ss].second and v[ee].second >= v[ss].second) cout << qnt+1 << endl;
else cout << "impossible\n";
}
}
