#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<ll>;
using vvl = vector<vll>;
using vb = vector<bool>;
using pll = pair<ll,ll>;
using vpl = vector<pll>;
using vvp = vector<vpl>;
#define f first
#define s second
#define all(v) v.begin(),v.end()
#define pb push_back
vll val;
struct seg{
ll n;
vpl bl;
seg(ll n):n(n){
bl = vpl(n*2, {1e9,1e9});// {who, val}
}
pll com(pll a, pll b){
if(a.s<b.s)return a;
return b;
}
void upd(ll i, pll x){
i+=n;
bl[i] = com(bl[i], x);
for(i/=2; i>0;i/=2){
bl[i] = com(bl[i*2], bl[i*2+1]);
}
}
ll que(ll a, ll b){
pll ans = {1e9,1e9};
for(a+=n,b+=n;a<=b;a/=2,b/=2){
if(a%2==1)ans = com(ans, bl[a++]);
if(b%2==0)ans = com(ans, bl[b--]);
}
return ans.f;
}
};
ll fd(ll a){
return lower_bound(all(val),a)-val.begin();
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(NULL);
ll n, q, s, e, f=20;
cin >> n >> q;
vpl ev(n);
set<ll> d;
for(pll& i:ev){cin >> i.s >> i.f;d.insert(i.f);d.insert(i.s);}
for(ll i:d)val.pb(i);
ll N = 1<<(32-__builtin_clz(val.size()));
seg *S = new seg(N);
vvl nxt(f, vll(n));
for(ll i = 0; i < n; ++i){
S->upd(fd(ev[i].f), {i, fd(ev[i].s)});
}
for(ll i = 0; i < n; ++i){
nxt[0][i] = S->que(fd(ev[i].s), fd(ev[i].f));
}
for(ll h = 1; h < f; ++h){
for(ll i = 0; i < n; ++i){
nxt[h][i] = nxt[h-1][nxt[h-1][i]];
}
}
while(q--){
cin >> e >> s;s--;e--;
if(ev[s].f<ev[e].f){cout << "impossible\n";continue;}
ll ans = 1e9, cur=0;
for(ll h = f-1; h >= 0; --h){
if(ev[nxt[h][s]].s<=ev[e].f)ans = min(ans, cur+(1<<h)+1);
else{
cur+=(1<<h);
s = nxt[h][s];
}
}
if(ev[s].s<=ev[e].f)ans = min(ans, 1ll);
if(s==e)ans=0;
if(ans==1e9)cout << "impossible\n";
else cout << ans << "\n";
}
}
