#include <bits/stdc++.h>
using namespace std;
#define ar array
#define int long long
#define ld long double
const int N = 5e5 + 20;
const int LOG = 21;
const int INF = 1e17;
namespace seggy{
ar<int, 2> s[4 * N];
void build(int k,int tl,int tr){
s[k] = {-1, -1};
if(tl == tr)return;
int tm = (tl + tr) / 2;
build(k * 2, tl, tm);
build(k *2 + 1,tm + 1, tr);
}
void upd(int k,int tl,int tr,int p,ar<int, 2> v){
if(tl == tr){
s[k] = max(s[k], v);
return;
}
int tm = (tl + tr) / 2;
if(p <= tm)upd(k * 2,tl, tm, p, v);
else upd(k * 2 + 1, tm + 1, tr, p, v);
s[k] = max(s[k * 2], s[k * 2 + 1]);
}
ar<int, 2> qry(int k,int tl,int tr,int l,int r){
if(l > tr || tl > r)return {-1, -1};
if(l <= tl && tr <= r)return s[k];
int tm = (tl + tr) / 2;
return max(qry(k * 2,tl, tm, l,r), qry(k *2 + 1, tm + 1, tr, l, r));
}
}
signed main(){ios::sync_with_stdio(false);cin.tie(0);
int n, q;
cin>>n>>q;
int s[n], e[n];
vector<int> v;
for(int i = 0;i < n;i++){
cin>>s[i]>>e[i];
v.push_back(s[i]);v.push_back(e[i]);
}
sort(v.begin(), v.end());
v.erase(unique(v.begin(), v.end()), v.end());
int m = v.size();
seggy::build(1, 0, m - 1);
for(int i = 0;i < n;i++){
s[i] = lower_bound(v.begin(), v.end(), s[i]) - v.begin();
e[i] = lower_bound(v.begin(), v.end(), e[i]) - v.begin();
seggy::upd(1, 0, m - 1, s[i], {e[i], i});
}
int up[n][LOG];
for(int i = 0;i < n;i++){
ar<int, 2> j = seggy::qry(1, 0, m-1, s[i], e[i]);
up[i][0] = j[1];
}
for(int j = 1;j < LOG;j++){
for(int i = 0;i < n;i++){
up[i][j] = up[up[i][j - 1]][j - 1];
}
}
while(q--){
int x,y;
cin>>x>>y;
--x, --y;
int ans = 0;
for(int i = LOG - 1;i >= 0;i--){
int j = up[x][i];
if(e[j] < s[y]){
x = j;
ans |= (1 << i);
}
}
if(x == y)cout<<ans<<'\n';
else{
if(s[y] > e[x]){
x = up[x][0];
++ans;
}
if(s[y] <= e[x] && e[x] <= e[y])cout<<ans + 1<<'\n';
else cout<<"impossible\n";
}
}
}
