#include <bits/stdc++.h>
using namespace std;
typedef vector<int>vi;
#define pb push_back
#define all(x) begin(x), end(x)
#define sz(x) (int)x.size()
#define FOR(i,a,b) for(int i=a; i<b; i++)
#define ROF(i,a,b) for(int i=b-1; i>=a; i--)
template<class T> bool ckmin(T& a, const T& b) { return a > b ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
const int INF=2e9;
const int MX=1e5+10;
void IO() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
}
/////////////////////////ONLY CLEAN CODES ALLOWED/////////////////////////
int N,Q;
vi L(MX), R(MX);
vi adj[MX];
int main(){
IO();
cin>>N>>Q;
FOR(i,1,N+1) cin>>L[i]>>R[i];
FOR(i,1,N+1) FOR(j,1,N+1) if(i!=j){
if(R[i]>=L[j] && R[i]<=R[j]){
if(sz(adj[i])){
int k=adj[i].back();
if(R[k]<R[j]){
adj[i].pop_back();
adj[i].pb(j);
}
}
else adj[i].pb(j);
}
}
vector<vi> dist(N+1, vi(N+1,INF));
FOR(s,1,N+1){
dist[s][s]=0;
queue<int>q;
q.push(s);
while(sz(q)){
int u=q.front();
q.pop();
for(int v: adj[u]) if(dist[s][v]==INF){
dist[s][v]=dist[s][u]+1;
q.push(v);
}
}
}
while(Q--){
int s,e; cin>>s>>e;
if(dist[s][e]==INF) cout << "impossible" << endl;
else cout << dist[s][e] << endl;
}
}
